IIHS research bibliography

IIHS has been conducting research for more than 50 years. Papers published in copyrighted publications such as books, journals and conference proceedings are available upon request, but their contents may not be redistributed or republished without consent of the publishers. Unpublished and noncopyrighted reports are available for download, and their contents may be redistributed and republished with attribution.

Alcohol-impaired driving: the problem and some countermeasures

It has long been known that alcohol impairment among drivers and pedestrians is a major factor in serious motor vehicle crashes. Institute research undertaken during recent years has been designed to extend this basic knowledge and to fill in some gaps. Specifically, the following questions have been addressed.

Motorcyclists, pedestrians, and alcohol

Baker, Susan P.Proceedings of the 7th International Conference on Alcohol, Drugs, and Traffic Safety 1979

Abstract

In connection with highway travel, the ultimate goal is to reduce the number of highway deaths and the number and severity of injuries that are at least partly attributable to alcohol and other drugs. It is important that we should keep sight of the wide variety of available approaches. They can be divided into four categories, none of which is sufficient by itself, none of which should be excluded: first, reductions in the amount or changes in the patterns of use of alcohol and other drugs; second, reductions in the degree of impairment produced when alcohol and other drugs are used; third, reductions in the amount of travel or changes in the characteristics of travel by people who are impaired by alcohol and other drugs; and fourth, reductions in the probability of injury and severity of its consequences when impaired people use our roadways, either as vehicle operators or as pedestrians.

The effect of alcohol and smoking on testosterone function and aggression in chronic alcoholics

Forty alcoholics without other significant medical or psychiatric problems were studied on a research ward for two weeks. All subjects abstained from alcohol and cigarettes during the first week; 30 randomly selected subjects were permitted unlimited alcohol and/or cigarettes during the second week. Plasma testosterone levels were normal during the first week but decreased rapidly and significantly in those subjects allowed alcohol. A variety of measures of affect failed to show a significant correlation between hostility/aggression and plasma testosterone levels or alcohol ingestion.

Comments on "Evidence of alcohol and drug impairment obtained after arrest"

Evidence of alcohol or drug impairment is an essential element of a criminal prosecution for driving while impaired (DWI) by alcohol or drugs. Such evidence, or the refusal to provide such evidence, also is essential in the administrative license sanction area. Evidence of impairment includes: (1) Chemical testing for alcohol or drugs (obtaining and analyzing blood, breath, or urine samples); (2) Observations of the driver including (a) physical condition, appearance, and behavior and (b) physiological and behavioral tests indicating possible impairment; and (3) Statements by the driver admitting alcohol and or drug consumption and impairment. Chemical testing for the presence and amount of alcohol or drugs in a driver's body is the most important type of evidence of impairment. However, when a driver refuses to provide such evidence, the prosecution of an individual for DWI is often limited to the other types of impairment evidence listed above. This paper discusses post-arrest impediments to obtaining evidence of impairment of a driver arrested for DWI, the dynamics and incidence of chemical test refusal, procedures for reducing the refusal rate or reducing the effectiveness of refusal in preventing a conviction for DWI, and the problems and possible solutions to the issue of obtaining chemical tests for impairment from injured drivers receiving treatment at emergency medical facilities after involvement in motor vehicle crashes.

Comments on "Identification of alcohol impairment on initial interview"

After a vehicle is stopped, the next step in the process is the driver interview, typically conducted by the officer at the driver-side window of the vehicle. The purpose of this interview, in conjunction with other observations made by the officer, is to determine whether or not there is reasonable suspicion to proceed with an impaired driving investigation. If yes, the driver is typically asked to step out of the vehicle and submit to field sobriety testing. If no, no further impaired driving investigation would likely be conducted. The objective of this paper is to summarize available research on process and procedure as they relate to an impaired driving investigation at the driver-side window immediately following a vehicle stop. Throughout this paper, the term "DUI" encompasses operating under the influence; driving under the influence; operating while intoxicated; operating under the influence; operating at a blood alcohol concentration above 0.08 or 0.10 percent, and similar charges. It should be noted that this general use of the term "DUI" obscures important distinctions between each charge as defined uniquely in the laws of each state.

Issues and methods in the detection of alcohol and other drugs

The central question of this workshop is: How can it reliably be established that a person has consumed alcohol and/or other drugs in amounts that are illegal and/or may cause harm to that person or others? Many people think of this as a relatively easy task, conjuring up images of the “falling down drunk,” although even this obvious display may be something else, for example, diabetic shock. The reality is that even when people have high blood alcohol concentrations (BAC) known to cause signi cant impairment, it can be difficult for experts and laypersons alike to detect alcohol, especially among seasoned users and among people who wish to remain undetected. Detecting drugs other than alcohol presents its own set of problems, and in many cases the behavioral cues are less obvious than when alcohol has been consumed. The workshop’s focus is on police detection of alcohol and other drugs among drivers of private motor vehicles.

The role of passive alcohol sensors in detecting alcohol-impaired drivers at sobriety checkpoints

Sobriety checkpoints are a deterrent to alcohol-impaired driving if they are conducted often. For a sobriety checkpoint to be an effective deterrent, though, the police officers must be reasonably competent in identifying the alcohol-impaired drivers passing through it. Officers have limited time and few cues on which to make judgments about impairment. This study examines the use of passive alcohol sensors by police officers as a screening device to provide an objective indication of alcohol in the driver's breath. Police officers using standard checkpoint procedures identified 26 percent of drivers with blood alcohol concentrations between 0.05 percent and <0.10 percent and 55 percent of drivers with blood alcohol concentrations of 0.10 percent or higher. Officers using the passive alcohol sensors had detection rates of 39 percent and 71 percent, respectively.

Skills performance at low blood alcohol levels

The effect of low blood alcohol levels (BALs) on driving skills performance was examined experimentally. Ten moderate drinkers were tested on divided-attention and information processing tasks at BALs of zero, 15, 30, 45 and 60 mg/dl. All response measures showed evidence of impairment beginning at 15 mg/dl and increasing impairment with increasing BALs. Thus there is no evidence that low or very low BALs improve performance on driving-related skills, as has sometimes been suggested.

Detection of drinking: a neglected element in DWI enforcement

Voas, Robert B.Insurance Institute for Highway Safety October 1983

Abstract

A strong emphasis is being placed on general deterrence to drunken driving by the National Highway Traffic Safety Administration, the federal government, through the President’s Commission on Drunk Driving and by the states, through new legislation strengthening drunk driving laws, and appropriations providing for increased enforcement effort. While considerable emphasis is being given to enforcement and to producing general deterrence, relatively little has been done to study the nature of the general deterrent effect or to produce improved enforcement technology. There are, however, three notable exceptions to this general statement: 1) breath test development companies have produced small, portable preliminary test devices which are highly accurate; 2) under a NHTSA contract (Harris, et al., 1980), the driving behaviors which are most likely to indicate that the vehicle operator is impaired have been studied and compiled in a manual for traffic enforcement officers; and, 3) with NHTSA support (NHTSA, 1982), a new sobriety testing technique making use of a Nystagmus (small involuntary movements of the eye) has been developed and embodied in a training program for application to officers on DUI assignment.

Alcohol, marihuana and skills performance

There now exists a large body of studies which demonstrate that the ingestion of either alcohol or mairhuana will produce decrements in the performance of skills which are important for man-machine interactions such as driving. In light of evidence of an increase in the combined use of these substances, attention currently is being given to the effects on driving related skills of alcohol and marihuana together. In a study by Manno et al. (1971) the combined alcohol and marihuana treatment produced greater impairment of pursuit tracking and mental arithmetic tasks than did either drug alone. Similarly, Macavoy and Marks (1975) reported increased impairment of visual signal detection under combined alcohol-marihuana treatment. In an extensive examination of this issue by Chesher and colleagues (Chesher et al., 1976, 1977; Belgrave, 1979) combined drug treatments were examined with a test battery which included standing steadiness, pursuit rotor, reaction time, and arithmetic and language tasks. The results were highly dependent on the task under examination. Under the combined treatment most of the psychomotor tasks showed a roughly additive increase in impairment over the effects of the single treatments. On the other hand, performance of the cognitive tasks was not more impaired by the combined treatment than by marihuana alone, but the effect was greater than for alcohol alone. In the current study, a test battery, including skills performance tasks and cognitive tasks, was examined under the single and combined treatments of 0.58 g alcohol/kg bodyweight. The marihuana and the alcohol treatment levels are typical of amounts commonly used by moderate users of alcohol and moderately heavy users of marihuana.

The effects of alcohol and caffeine, alone and in combination, on skills performance

The data from these experiments are consistent in indicating that caffeine can offset to some extent the impairment by alcohol of certain components of driving performance. Clearly, tracking, visual search and reaction time exhibited the caffeine antagonism of alcohol impairment. However, the rate of information processing task failed to show an improvement under the caffeine treatment, demonstrating that the effects of caffeine are specific to behavioral mechanisms.

Effects of diphenhydramine and alcohol on skills performance

Twelve men were subjects in a repeated measures experiment on the effects on performance of diphenhydramine, alcohol, and diphenhydramine and alcohol in combination. Behavioral measures included compensatory tracking, a divided attention task, information processing rate, and critical tracking. Performance impairment occurred under all treatments with an additive effect under the combined drug-alcohol treatment.

Effects of diazepam and alcohol on skills performance

Performance scores for all tasks in a behavioral test battery were lower under diazepam than under placebo. The diazepam dose of .0726 mg/kg bodyweight significantly impaired an information processing task and tracking performance under divided attention conditions. An aclohol dose of 0.58 gm/kg bodyweight significantly impaired performance of all response measures. The combined diazepam-alcohol treatment produced greater performance decrements than either treatment alone. Moderate doses of diazepam and alcohol, alone and in combination impaired performance on a battery of tests which represent the skills requirements of driving.

Feasibility of determining blood alcohol concentrations in social drinking settings

The effects of alcohol and valium, singly and in combination, upon driving-related skills performance

Moskowitz, Herbert A.; Burns, Marcelline M.Proceedings of the 21st Annual Conference of the American Association for Automotive Medicine 1977

Abstract

Twelve male participants, ages 21-42, were tested in four laboratory sessions under diazepam alone, alcohol alone, diazepam and alcohol in combination, and placebos. The test battery included pursuit tracking, visual divided attention, and visual backward masking. Performance deficits were found under the separate treatments, with an additive effect under the combined alcohol-diazepam treatment.

Information processing was tested in 12 male subjects after smoking marihuana containing 0, 10, or 20 mg. of delta-9-tetrahydrocannabinol (THC) in three consecutive experimental sessions according to a Latin square protocol. Successful dose control was indicated both by the dose-related linear increase observed in heart rate and by preliminary assays of THC metabolites excreted in the urine. During tachistoscopic presentation of varying numbers of circles, statistically significant decrements in information processing occurred as a function of THC dosage. However, adding irrelevant information (triangles) to the display of circles eliminated effects of marihuana on accuracy of counting. Complex reaction times for oddity discrimination increased significantly only after the high dose. Nonetheless, both the social and high doses inappropriately inhibited the general tendency to respond to changing stimuli during oddity discrimination. Marihuana had no effect on field-dependence as measured by the Rod-and-frame test.

Plasma alcohol, smoking, hormone concentrations and self-reported aggression: a study in a social drinking situation

Plasma alcohol concentrations and the number of cigarettes smoked by men during social-drinking situations were significantly related to change in testosterone levels. Age, height, plasma alcohol and smoking were related to self-reports of prior assault and verbal aggression. Aggression was not related to testosterone concentration.

Screening drivers for alcohol -- an application of Bayes' formula

This paper shows that the criteria under which the drivers can be required to take a breath-alcohol screening test become extremely important when the screening test results are subject to some error. Combining the data from two published studies clearly illustrates the excessively high rates of false arrests which may occur if poor screening methods are employed to screen randomly selected drivers.

An evaluation of some qualitative breath screening tests for alcohol

O'Neill, Brian; Prouty, Richard W.Proceedings of the 15th Annual Conference of the American Association for Automotive Medicine 1972

Abstract

An evaluation of inexpensive, disposable devices for breath testing of blood alcohol concentrations shows that such devices produce high numbers of erroneous results. The evaluation was conducted by the State Toxicology Laboratory of North Dakota State University and the Insurance Institute for Highway Safety. Volunteers from the North Dakota and Minnesota highway patrols served as subjects and tube readers for the study. A total of eight disposable screening devices from four manufacturers were evaluated. The devices tested were the Alcolyser H, Alcolyser (Iowa type), Alcolyser 100, Becton-Dickinson Device 1, Becton-Dickinson Device 2, the Kitigawa Drunk-O-Tester, the Sober-Meter SM-1, and the Sober-Meter SM-6. All of the disposable screening devices tested are similar in design and operation. They are commonly used for prearrest screening tests to indicate whether the blood alcohol concentration of a suspect is above or below the legal limit. Subjects blow either into a balloon from which the breath sample is passed through the tube containing alcohol-sensitive reagent, or directly through the tube into a balloon. The reagent changes color from yellow-orange to green in proportion to the concentration of alcohol in the breath. Study results indicate that these devices produce high numbers of erroneous findings. Both false positive and false negative readings can be obtained with the tested devices.

Comments with respect to highway safety research with particular reference to "chemical tests"

Haddon, William Jr.Insurance Institute for Highway Safety October 1961

Abstract

It would be impossible in the time available here to discuss or even to list the many ways in which chemical tests for the presence of alcohol have been, are being and will in the future be used for highway safety research. Such purposes relate to the entire gamut of questions which arise in connection with the uses and misuses of motor vehicles. This follows from the remarkable prominence of the use of alcohol as a factor in motor vehicle accidents, both fatal and non-fatal. As a result the scientific evaluation of almost any other aspect of motor vehicle accident causation requires a determination of the extent of its relationship with the drinking-driving, drinking-accident problem. In view of this, it is noteworthy that in a number of recent, uncontrolled and controlled investigations seeking causes of accidents this has not been done with even minimum adequacy. Fundamentally considered, the “Chemical Tests”, as they are referred to here, are merely a tool, a yardstick, available for the measurement of one characteristic of drivers whether under experimental or non-experimental conditions. There is nothing magical, or unique, about these tests -- they have many parallels in related fields, notably in forensic and clinical medicine – and their use requires, regardless of the purpose for which they are employed, the same competence, care and intelligence as do such other analytical procedures; requirements which must be observed for the work in question to be both scientifically acceptable and practically useful.

Fatally injured pedestrians and bicyclists in the United States with high blood alcohol concentrations

Objective: Little research has focused on the problem of alcohol impairment among pedestrians and bicyclists in the United States. The aim of the current study was to investigate the prevalence, trends, and characteristics of alcohol-impaired fatally injured pedestrians and bicyclists.

Methods: Data from the Fatality Analysis Reporting System (FARS) were analyzed for fatally injured passenger vehicle drivers, pedestrians, and bicyclists 16 and older during 1982-2014. Personal, roadway, and crash characteristics were examined for pedestrians and bicyclists killed in crashes during 1982-86 and 2010-14, and logistic regression models examined which characteristics were associated with high blood alcohol concentrations (BACs) among these road users.

Results: The percentage of fatally injured pedestrians with high BACs (=0.08 g/dL) declined from 45 percent in 1982 to 35 percent in 2014. The percentage of fatally injured bicyclists with high BACs declined from 28 percent in 1982 to 21 percent in 2014. By comparison, the percentage of fatally injured passenger vehicle drivers with high BACs declined from 51 percent in 1982 to 32 percent in 2014. During the study periods, the largest reductions in alcohol impairment among fatally injured pedestrians and bicyclists were found among ages 16-20. During the most recent study period (2010-14), fatally injured pedestrians and bicyclists ages 40-49 had the highest odds of having a high BAC, compared with other age groups.

Discussion: A substantial proportion of fatally injured pedestrians and bicyclists have high BACs, and this proportion has declined less dramatically than for fatally injured passenger vehicle drivers during the past three decades. Most countermeasures used to address alcohol-impaired driving may have only limited effectiveness in reducing fatalities among alcohol-impaired pedestrians and bicyclists. Efforts should increase public awareness of the risk of walking or bicycling when impaired, and further research should evaluate the effectiveness of potential countermeasures directed at alcohol-impaired pedestrians and bicyclists.

Profile of fatally injured pedestrians and bicyclists in the United States with high blood alcohol concentrations

Background: In the United States, little research has focused on the problem of alcohol impairment among pedestrians and bicyclists.

Aims: The aim of this study was to investigate the prevalence, trends, and characteristics of alcoholimpaired fatally injured pedestrians and bicyclists.

Methods: The study analyzed 1992-2011 data from the Fatality Analysis Reporting System (FARS), a census of U.S. fatal motor vehicle crashes. Personal characteristics, roadway type, and other factors were examined among fatally injured pedestrians and bicyclists 16 and older who had high blood alcohol concentrations (BACs).

Results: The number of pedestrians killed in motor vehicle crashes decreased and the number of bicyclists killed in motor vehicle crashes increased among ages 16 and older during the study period; however, the percentages with high BACs changed little. Among fatally injured pedestrians, the percentage with BACs =0.08% was 39% in 1992 and 37% in 2011. Among fatally injured bicyclists, the percentage with BACs =0.08% was 26% in 1992 and 25% in 2011. During the most recent 5 years of data (2007-11), 20,326 pedestrians 16 and older were fatally injured, and 37% of them had BACs =0.08%. The percentage of fatally injured pedestrians with BACs =0.08% was higher among males (43%) and ages 21-49 (47-50%), on weekends (49%), and in crashes occurring at night, especially during midnight-2:59 a.m. (60%). During the most recent 5 years of data (2007-11), 2,907 bicyclists 16 and older were fatally injured in crashes with motor vehicles, and 26% of them had BACs =0.08%. The percentage of bicyclist deaths with BACs =0.08% was highest during midnight-2:59 a.m. (49%) and among ages 30-49 (34-36%).

Conclusions: A substantial proportion of fatally injured pedestrians and bicyclists had high BACs, and this proportion has changed little during the last two decades. To the extent that alcohol impairment of pedestrians and bicyclists contributes to their deaths, countermeasures addressing alcohol consumption among these groups are needed.

U.S. trends in late-night weekend alcohol-related fatal crashes and drinking and driving

Background: The proportion of U.S. drivers in fatal crashes with blood alcohol concentrations (BACs) of 0.08% or higher declined substantially from 1982 through the mid-1990s but changed little since, whereas periodic national roadside surveys reported large declines in alcohol use.

Aims: To examine possible explanations for the apparent disconnect between trends in drinking and driving and trends in the proportion of drivers with BACs =0.08% in fatal crashes.

Methods: The study looked at data from national roadside surveys conducted on Friday and Saturday late nights (10 p.m.-3 a.m.) in 1986, 1996, and 2007 and data on fatal crashes for these times and years. Differences in the roadside survey samples and protocols were examined, as were trends in rates of BACs =0.08% among driver sub-groups in the roadside surveys and FARS.

Results: Even after adjustments to the roadside surveys for differences in sampling and weighting, there were large declines in drivers with BACs =0.08% (5.4% in 1986, 4.2% in 1996, 2.6% in 2007) not reflected in rates of drivers with BACs =0.08% in fatal crashes (55.3% in 1986, 52.1% in 1996, 49.7% in 2007). Drivers with BACs =0.08% in fatal crashes were more likely than other drivers to drive older vehicles, be speeding, be unrestrained, and have prior moving violations and crashes/suspensions. Except for belt use, the differences were fairly consistent over time. Belt use increased more slowly among drivers with BACs =0.08%.

Conclusions: Different methodologies of roadside surveys do not appear to explain why alcohol impairment in fatal crashes has declined much less than the rate of drinking drivers in general. Trends generally were similar for sub-groups of drivers in roadside surveys and in fatal crashes. The fact that drinking drivers have been slower to buckle up appears to account for some of the discrepancy in trends, but there also appear to be other unknown factors.

Although it is well-known that alcohol-impaired driving increases crash risk, the number of crash deaths specifically attributable to alcohol-impaired driving is less well known. Many fatal crashes occur with sober drivers, and many fatal crashes of drinking drivers would still have occurred if they had not been drinking. In order to understand what is possible with different countermeasures — for example, those aimed at convicted offenders or high blood alcohol concentration (BAC) drivers versus those targeted at the general population of drivers — it is important to know how much of the problem is accounted for by these different target populations. In this paper we describe a calculation procedure for estimating the number of crash fatalities in the 2010 Fatality Analysis Reporting System (FARS) attributable to different driver BACs. The procedure first classifies all fatalities by the highest BAC for driver(s) involved in the crash. Then, using the risk curve developed by Zador et al., the number of fatalities specifically attributable to the high BACs is estimated. It is estimated that drivers with BACs at or above 0.08 g/dL were involved in the deaths of 10,228 road users in the United States in 2010 and that, had all these drivers had BACs below 0.08 g/dL, 7,082 of these deaths would have been prevented — this is the number attributable directly to BACs at or above 0.08 g/dL. Had all drivers had BACs below 0.05 g/dL, an estimated 8,770 deaths would have been prevented. If all drivers in 2010 had had zero BACs, as many as 10,600 deaths would have been prevented. If all drivers with at least one alcohol-impaired driving conviction within 3 years prior to the crash were restricted to BACs below 0.08 g/dL, 552 deaths could have been prevented in 2010.

Hardcore drinking drivers and other contributors to the alcohol-impaired driving problem: need for a comprehensive approach

Objective: Understanding the hardcore drinking driver concept in the context of the alcohol-impaired driving problem.

Method: Review of the relevant literature.

Results: As progress against alcohol-impaired driving slowed in the early 1990s, public and political attention turned to "hardcore" drinking drivers, and they have been a priority for the past 15 years. Though intuitive, the hardcore concept has been difficult to conceptualize. Its definition of hard-to-change chronic heavy drinking drivers focuses on a group that is not easily identifiable and ignores many who account for a large portion of alcohol-impaired driving crashes. These include drivers who drink heavily on occasion and drivers who drink at more moderate levels that elevate crash risk. Emphasis on the hardcore has focused attention on the small proportion of drinking drivers who have been detected and arrested, whereas the vast majority of drinking drivers go undetected. Some countermeasures aimed at the hardcore group have been effective in reducing recidivism, but attention and resources also need to be given to general deterrent initiatives (e.g., 0.08 g/dL, sobriety checkpoints, administrative license suspension). There has been no reduction in the overall alcohol-impaired driving problem since the mid-1990s.

Conclusion: Reductions in the alcohol-impaired driving problem require that attention be focused on all relevant target groups. Some benefits could accrue by recognizing that countermeasures developed for hardcore drinking drivers, such as alcohol ignition interlocks and vehicle or plate impoundment, might also be effective with more numerous first-time offenders. However, such strategies are likely to be most effective against recidivism (specific deterrence). Greater gains could be achieved through general deterrent efforts (increasing the real and perceived risk of arrest and punishment to all drinking drivers), along with application of public health measures designed to reduce overall consumption. Additional ways need to be found to separate drinking and driving, either through cultural changes in drinking and/or driving behavior or, in the future, with the use of technology that can make vehicles inoperable by drivers with illegal blood alcohol concentrations.

Although it is well-known that alcohol-impaired driving increases crash risk, the number of crash deaths specifically attributable to alcohol-impaired driving is less well known. Many fatal crashes occur with sober drivers, and many fatal crashes of drinking drivers still would have occurred if they had not been drinking. In order to understand what is possible with different countermeasures — for example, those aimed at convicted offenders or high blood alcohol concentration (BAC) drivers versus those targeted at the general population of drivers — it is important to know how much of the problem is accounted for by these different target populations. In this paper we describe a calculation procedure for estimating the number of crash fatalities in the 2005 Fatality Analysis Reporting System (FARS) attributable to different driver BACs. The procedure first classifies all fatalities by the highest BAC for driver(s) involved in the crash. Then, using the risk curve developed by Zador et al.,1 the number of fatalities specifically attributable to the high BACs is estimated. It is estimated that drivers with BACs at or above 0.08 g/dL were involved in the deaths of 12,945 road users in the United States in 2005 and that, had all these drivers had BACs below 0.08 g/dL, 8,916 of the deaths would have been prevented – this is the number attributable directly to BACs at or above 0.08 g/dL. Had all drivers had BACs below 0.05 g/dL, an estimated 11,100 deaths would have been prevented. If all drivers in 2005 had had zero BACs, as many as 13,452 deaths would have been prevented. If all drivers with at least one alcohol-impaired driving conviction within 3 years prior to the crash were restricted to BACs below 0.08 g/dL, 777 deaths could have been prevented in 2005.

Role of cannabis and benzodiazepines in motor vehicle crashes

Alcohol is known to increase crash risk, but the evidence for other drugs is much less clear. Studies have been hampered by measurement issues and the small proportions of drivers found with drugs other than alcohol, especially drugs in the absence of alcohol. Cannabis and benzodiazepines (BZDs) are the two drugs other than alcohol most often found among crash-involved drivers. Both have been found to impair driving skills measured in the laboratory, but there are few adequate studies assessing their contribution to crashes, and these studies have mixed results. The weight of the evidence suggests that BZDs increase crash risk, in particular long-acting BZDs prescribed for medical use, at least for the first weeks of use. Further studies of cannabis and BZDs are needed to clarify their contribution to the highway safety problem.

Blood alcohol concentrations (BACs) of fatally injured passenger vehicle drivers in the Unite States were used to examine the current and historical distributions of BACs and the characteristics of fatally injured drivers by BAC categories, including those with very high BACs. All categories of illegal BACs (0.08% or higher) declined substantially from 1982 to 2002, and declines were similar across BAC categories. Among illegally impaired drivers, the prevalence of several driver and crash characteristics increased systematically, but gradually, with increasing BACs. This study does not support the claim that "hard core drinking drivers" have become a larger part of the problem and have been unaffected by general deterrent approaches.

Drinking histories of fatally injured drivers

Context: About 30% of drivers killed in crashes have high blood alcohol concentrations (BACs) of 0.10+ g/dl. There is a question about whether these drivers primarily are problem drinkers who chronically drink and drive—the so-called hard core drinking drivers.

Objective: To investigate drinking histories of fatally injured drivers in relation to their BACs. Design and participants: Retrospective cohort study of 818 fatally injured drivers who were included in the 1993 National Mortality Followback Survey (a national sample of US deaths in which next of kin were interviewed) and whose BACs were recorded by the Fatality Analysis Reporting System, a census of US traffic deaths. Main outcome measure: Problem drinking indicators.

Results: At least one indicator of potential problem drinking, primarily heavy drinking, was reported for 68% of drivers with very high BACs (0.15+ g/dl), 41% with BACs of 0.10–0.14 g/dl, 32% with BACs of 0.01–0.09 g/dl, and 7% with zero BACs. Spouses provided more credible responses than other relatives: they were more likely to report at least occasional drinking and driving among deceased drivers with high BACs. For the most direct signs of problem drinking (described as a problem drinker during the last month of life or frequently driving after having five or more drinks), spousal reports suggested the prevalence of problem drinking among drivers with very high BACs was 22% (having both indicators), 32% (frequently driving after having five or more drinks), 44% (described as problem drinker), or 57% (having either indicator).

Conclusions: Drivers with BACs of 0.10+ g/dl were far more likely than sober drivers to be described as having markers of problem drinking. However, many did not have indicators suggestive of problem drinking. In addition to programs focused on repeat offenders or problem drinkers, countermeasures such as sobriety checkpoints that target a broader spectrum of drinking drivers are appropriate.

Factors associated with high blood alcohol concentration among fatally injured drivers in the United States, 1991

Addresses the current status of the alcohol-related motor vehicle crash problem in the US. Blood alcohol concentration (BAC) test results were obtained for 6,632 fatally injured drivers of passenger vehicles from 23 states, representing 32% of all passenger vehicle driver fatalities in the US in 1991. 40% of fatally injured passenger vehicle drivers had BACs =0.10%; 21% had very high BACs, =0.20%. Factors prominently associated with high alcohol involvement among fatally injured drivers were younger age, male gender, late night hours, lack of seat belt use, suspended/revoked licenses, fixed-object crashes, rollovers, and crashes on curves. 60% of fatalities among male drivers ages 21–40 yrs had BACs=0.10%, and this grouped comprised more than half of all high BAC drivers. In contrast, drugs other than alcohol are infrequently found among fatally injured drivers.

The 1980s decline in alcohol-impaired driving and crashes and why it occurred

Williams, Allan F.Alcohol, Drugs, and Driving 1992

Abstract

A decline in the percentage of fatally injured drivers with high blood alcohol concentrations in the early 1980's is attributed to reduced alcohol consumption in general, the emergence of citizen activist groups, and the proliferation of effective laws such as administrative license suspension and 21-year-old minimum alcohol purchase laws. The Fatal Accident Reporting System, a census of virtually all fatal crashes in the United States on public roads, contains information on blood alcohol test results for people in fatal crashes. Overall, the percentage of fatally injured drivers with blood alcohol concentrations at or above 0.10 percent declined from 50 percent in 1980 to 40 percent in 1990. Declines were greatest among passenger vehicle and tractor-trailer drivers; there were smaller declines for motorcyclists and pedestrians. Surveys undertaken in 1973 and 1986 to determine the incidence of alcohol-impaired drivers on weekend nights revealed a substantial reduction in the number of drivers with high blood alcohol concentrations over the 13-year period. The author postulates that the declines are due to changing social norms regarding health-related behavior, increased grass roots activism related to alcohol-impaired driving that has heightened public awareness of the problem and energized the activities of government and other public and private agencies, and the proliferation of effective laws. In the latter part of the 1980's, the percentage of fatally injured drivers with high blood alcohol concentrations stabilized and public attention to the problem waned. Progress in dealing with the problem of alcohol-impaired driving and crashes can be realized through wider implementation of effective laws, additional strategies not based on deterrence, and a resurgence in public focus on the problem.

Alcohol-related relative risk of fatal driver injuries in relation to driver age and sex

Zador, Paul L.Journal of Studies on Alcohol 1991

Abstract

The relative risks of fatal crash involvement at various blood alcohol concentrations (BACs) were examined using data on fatal driver injuries from the Fatal Accident Reporting System in conjunction with driver exposure data from the second national road-side breath-testing survey. Based on driver fatalities in single-vehicle crashes, it was estimated that each 0.02 percentage increase in the BAC of a driver with non-zero BAC nearly doubles the risk of being in a fatal crash. Crash risk was found to increase with increasing BAC among all of the six age and sex groups studied. At BACs in the 0.05-0.09 percent range, the likelihood of a crash was at least nine times greater than at zero BAC for all age groups. Younger drivers with BACs in the 0.05-0.09 range had higher relative risks than older drivers, and females had higher relative risks than males. At very high BACs (at or above 0.15 percent), the risk of crashing was 300 to 600 times the risk at zero or near-zero BACs. These relative risk estimates are considerably higher than estimated in other studies, but other studies have based their estimates on all crashes rather than single-vehicle crashes only. In this study, relative risks were also lower when based on driver fatalities in all crashes. However, when plausible assumptions were made about the BAC distributions of other participants in multiple-vehicle crashes (whose actual BAC is often unknown), the relative risks based on the maximum BAC of the crash participants were nearly as high as those estimated in single-vehicle crashes.

Alcohol-impaired driving and crashes involving alcohol in the United States during the 1970s and 1980s

Data from the United States Fatal Accident Reporting Systems (FARS) and roadside surveys were used to track changes in alcohol-impaired driving and crashes involving alcohol in the 1970s and 1980s. National roadside surveys conducted in 1973 and 1986 indicate that substantial reductions in drivers with high blood alcohol concentrations (BACs) on weekend nights occurred between those two dates. FARS data indicate that a substantial decrease in the percentage of fatally injured motor vehicle drivers with high BACs occurred in the past decade, although the problem is still large. This decrease has been very pronounced for some groups (e.g., youthful passenger vehicle drivers); there has been little or no change for other groups (e.g., motorcycle drivers. alcohol-impaired pedestrians). Research studies have indicated that specific legal actions (e.g., raising the minimum alcohol purchase age; administrative license suspension laws) have led to reductions in alcohol-related crashes. Attempts to quantify the role of government, private groups, and other likely contributors to the reductions are necessarily speculative. Because of data limitations. it is not possible to accurately or completely assess trends in alcohol-impaired driving and crashes for the 1970s and 1980s. Despite this lack. there is clear evidence that there have been substantial reductions during this period in alcohol-impaired driving and in fatal crash involvement of drivers impaired by alcohol. This evidence comes from two roadside surveys conducted during this period and from information obtained by some states on blood alcohol concentrations (BACs) of fatally injured drivers since the middle to late 1970s. These are the only reliable data readily available that can be used to track changes.

Fatal crash involvement and laws against alcohol-impaired driving

It is estimated that in 1985 about 1,560 fewer drivers were involved in fatal crashes because of three types of drinking-driving laws. The laws studied were per se laws that define driving under the influence using blood alcohol concentration (BAC) thresholds; laws that provide for administrative license suspension or revocation prior to conviction for driving under the influence (often referred to as "administrative per se" laws); and laws that mandate jail or community service for first convictions of driving under the influence. It is estimated that if all 48 of the contiguous states adopted laws similar to those studied here, and if these new laws had effects comparable to those reported here, another 2,600 fatal driver involvements could be prevented each year. During hours when typically at least half of all fatally injured drivers have a BAC over 0.10 percent, administrative suspension/revocation is estimated to reduce the involvement of drivers in fatal crashes by about 9 percent; during the same hours, first offense mandatory jail/community service laws are estimated to have reduced driver involvement by about 6 percent. The effect of per se laws was estimated to be a 6 percent reduction during hours when fatal crashes typically are less likely to involve alcohol. These results are based on analyses of drivers involved in fatal crashes in the 48 contiguous states of the United States during the years 1978 to 1985.

We collected data on all residents of San Diego County, California who were hospitalized for or died from a brain injury in 1981. The objectives were to assess the frequency of blood alcohol concentration (BAC) testing and the associations of BAC prevalence with the external cause of the brain injury and case outcome. We found that high BAC levels were most frequent among brain-injured subjects between the ages of 25 and 44 and among those subjects involved in motor vehicle crashes and assaults. Contrary to expectations, injury severity and hospital mortality were inversely related to BAC level, controlling for other predictors. We believe that these inverse associations might be due to differential rates of BAC testing by severity. Among brain-injured survivors with more severe injuries, however, we found that BAC level was positively associated with the prevalence of physician-diagnosed neurological impairment at discharge and with the length of hospitalization.

Age differences of arrested and crash-involved drinking drivers

Voas, Robert B.; Williams, Allan F.Journal of Studies on Alcohol May 1986

Abstract

Studies were reviewed to determine the extent to which drivers arrested for driving while intoxicated (DWI) and crash-involved drivers impaired by alcohol are similar in age. Data indicate that younger drivers are substantially underrepresented in the DWI arrest population relative to their presence in the alcohol-related crash population. Overall, the proportion of arrested drivers less than age 20 was only one-fourth to one-third the proportion of these drivers involved in fatal crashes, and for those aged 20-29 it was two-thirds to three-fourths. The reasons for the underrepresentation of young drivers in the arrested population are not fully known and require further study. Youthful drivers constitute the major part of the alcohol-related crash problem, and effective ways to address this population most at risk should be sought.

Drugs in fatally injured young male drivers

One or more drugs were detected in 81 percent of 440 male drivers, aged 15-34, killed in motor vehicle crashes in California; two or more drugs were detected in 43 percent. Alcohol, the most frequently found drug, was detected in 70 percent of the drivers, marijuana in 37 percent, and cocaine in 11 percent. Each of 24 other drugs was detected in fewer than 5 percent. Except for alcohol, drugs were infrequently found alone; typically, they were found in combination with high blood alcohol concentrations. The causal role of drugs in crashes was assessed by comparing drivers with and without drugs in terms of their responsibility for the crash. Alcohol was associated with increased crash responsibility; the role of other drugs could not be adequately determined.

Effect of alcohol intoxication on the diagnosis and apparent severity of brain injury

Because alcohol intoxication is common among brain-injured patients, we performed this study to determine the extent to which alcohol alters the initial assessment of brain injury severity in these patients by depressing the level of consciousness. The Glasgow coma scale was used to measure the level of consciousness of 257 brain-injured adults admitted to the University of Virginia Hospital, both on arrival in the emergency room and 6 to 10 hours later. Improvement in the level of consciousness between the first and second measurements was significantly related to the blood alcohol concentration on admission. Patients with the highest blood alcohol concentrations showed the greatest improvement. Most of this effect occurred in patients with a blood alcohol concentration of 0.20% or higher. Alcohol intoxication is a potential source of bias in the clinical classification of brain injuries according to severity.

Automobile injuries related to drug abuse: an introduction to some of the basic considerations in prevention and research

Haddon, William Jr.Public Health Reports May/June 1984

Abstract

The paper holds that research and preventive measures to reduce injuries stemming from the use of alcohol and other drugs in relation to motor vehicles need not always be concerned with the pharmacologic agents in crash initiation and with the characteristics of their users. It would be more constructive from the standpoint of reducing injuries to give more emphasis to those characteristics of these events whose practical modification would ameliorate or completely prevent the final result, injury of given severity. The author presents a matrix to sort out the pieces of comprehensive data collection, research, preventive or other approach to losses associated with vehicle use. The matrix also points out where alcohol and other drugs fit in the overall picture. In this matrix, the general sequence of events which lead to given totals of losses on public or private balance sheets divides into three phases of interactions which are labelled PreEvent, Event, and PostEvent. The use of the matrix and the method is discussed.

Recent trends in fatal poisoning by opiates in the United States

Deaths in the United States classified as unintentional poisoning by drugs and medicaments fell from 14.7 per million population in 1975 to 8.8 in 1978, a 40 per cent decrease. Seventy-three per cent of this drop attributable to a reduction in deaths coded to opiates and intravenous narcotism. These two categories accounted for 38 per cent of all unintentional drug deaths in 1975 but only 15 per cent in 1978. There was no simultaneous increase in other drug-related deaths, including suicides, to account for the reduction in deaths coded to opiates. The highest mortality rates and the greatest variation in mortality during 1970-78 occurred in 20-29 year old non-White males. Racial and sex differences in opiate poisoning mortality, notable early in the decade, were greatly reduced by 1978 due to a relatively larger decline in mortality of males and non-Whites. Time trends in mortality from opiate poisoning appear to coincide with variations in the amount of heroin smuggled into the country.

Alcohol and motorcycle fatalities

A series of 99 fatal motorcycle crashes in Maryland was studied retrospectively, using police and medical examiner records. Blood alcohol concentrations were determined for 62 motorcycle drivers; measurable amounts of alcohol were found in two-thirds (41), and one-half (31) had illegally high concentrations of 100 mg/100 ml or more. The police report mentioned alcohol in only 9 instances. High blood alcohol concentrations were found most commonly among drivers age 20-34.

Alcohol in fatal tractor trailer crashes

Baker, Susan P.Proceedings of the 19th Annual Conference of the American Association for Automotive Medicine 1975

Abstract

A series of 150 fatal crashes involving tractor trailers was studied retrospectively. Twenty-five tractor trailer drivers and 63 drivers of other vehicles died and were tested for alcohol. About one-third in each group had blood alcohol concentrations of 0.10% by weight or more. Of 17 tractor trailer drivers apparently responsible for crashes, 8 had illegal alcohol concentrations (0.10% or more). Only 2% of the surviving drivers were charged with driving while intoxicated or impaired. Recommendations include implementation of the federal standard calling for quantitative tests for alcohol, where practicable, on all drivers (including surviving drivers) in crashes fatal to other persons.

Blood alcohol concentrations among Scandinavian drivers: data from the northern countries in international perspective

Ross, H. LaurenceBlutalkohol 1975

Abstract

The study reports the results of an effort to obtain data on blood alcohol concentrations among drivers in Norway, Sweden, Denmark and Finland. A search was made in these countries for studies performed on random or representative samples of (1) drivers fatally injured in crashes; (2) drivers seriously injured in crashes; and (3) drivers not involved in crashes. Only one study, limited to the city of Oslo, was found of drivers not involved in crashes. Sweden and Denmark have produced a scattering of broader but still incomplete studies of fatally injured drivers. A very few small-scale studies of seriously injured drivers were found in Sweden and Norway. Finland has produced no systematic studies on these topics. With some consistency the studies of fatally injured drivers suggest that elevated blood alcohol concentrations are less common in Sweden and Denmark than in the United States. The lone study of drivers not involved in crashes finds an extremely low prevalence of blood alcohol concentrations, in broad international context. However, the studies of injured drivers are not completely in accord with the picture based on the other populations. Although one can speculate that alcohol may be less prominent in motor vehicle crashes in Scandinavian countries than in many other countries, it is improper to infer without further information that the Swedish and Norwegian laws have produced this result.

Factors associated with alcohol and responsibility for fatal highway crashes

Waller, Julian A.Quarterly Journal of Studies on Alcohol 1972

Abstract

"Responsibility" for a crash was determined in 292 automobile drivers and 113 pedestrians, aged 15 and older killed in Alameda and Sacramento counties, Calif., during 1960-67. Pedestrians with blood alcohol concentrations (BAC) of 0.10% or over were responsible in 61% of the fatalities involving pedestrians. Among both pedestrians and drivers, whose with zero BAC were responsible in 47% of the cases; with 0.05 - 0.099% BAC, 79%; and with 0.15% or over, 89%. Among crash-responsible drivers and pedestrians aged 15-19, 44% had zero BAC and 20% had 0.10% or higher. Crash-responsible persons aged 20-59 had zero BAC in 26% and 0.10% or higher 64%, whereas 61% of crash-responsible persons aged 60 or over had zero BAC and 36% had 0.10% or higher. In 39 crashes both driver and passenger were killed; in 19 both had zero BACs or less than 0.05%; in 10 the passengers had substantialy lower BACs than the drivers; in 7 both had 0.10% BAC or higher; in 3 the driver had a lower BAC than the passengers. There was no difference between presumptive problem drinkers and others in crash responsibility either at zero BAC or at 0.10% and higher. BAC was more important in crash responsibility than vehicle age. In teen-agers, nearly all alcohol-related crashes occurred at night and at relatively low BACs.

Tattoos, alcohol, and violent death

Tattooed drivers fatally injured in crashes and tattooed homicide victims were more likely than their nontattooed counterparts to have contributed to the events leading to their deaths. Alcohol was correlated with presence of tattoos among drivers, and was a major factor in both forms of violent death.

Data from all highway fatalities of appropriate age and duration of survival in Alameda and Sacramento Counties. Calif., during January through March and October through December, 1960-67, were considered. Autopsies and blood alcohol determinations were completed on over 98 percent of the fatalities studied. Police reports were available in the coroners' offices. Police estimates of drinking by fatally injured drivers and pedestrians as recorded on police reports were compared with actual blood alcohol concentrations determined by the coroner. Over 20 percent of the time, alcohol was not mentioned in the police report. When alcohol was mentioned, its presence was usually underestimated. Alcohol was least likely to be reported among persons age 60 or older, pedestrians, nonresponsible fatalities, and drivers of new cars. It was most often reported among younger persons, drivers responsible for two-vehicle crashes, and drivers of older cars. One figure, four tables, and 11 references are included.

The role of alcohol in collisions involving trucks and the fatally injured

Waller, Julian A.Archives of Environmental Health January-June 1970

Abstract

The role of alcohol was studied in collisions in which drivers of large trucks and pickup trucks were involved either as fatally injured or surviving drivers. Drivers of large trucks almost always were the survivors, usually were not at fault, and probably had not been drinking in any of their crashes. The fatally injured drivers or pedestrians who initiated the crashes commonly had high blood alcohol concentrations. In contrast, drivers of pickup trucks more often were fatally injured in these crashes, frequently were responsible for their crashes, and usually had high blood concentrations. A comparison of blood alcohol concentrations and police assessments of drinking showed that an assessment that a person had not been drinking was correct in only 48% of cases in which the person or his vehicle was responsible for the crash, but in all cases reviewed where he was not responsible.

Alcohol and other factors in California highway fatalities

The role that alcohol plays in highway crashes from minor to fatal has been carefully demonstrated in a number of well-designed studies. Several studies have shown alcohol to be a factor in about half of fatal crashes to either drivers or pedestrians, and many of those who had been drinking have blood alcohol concentrations of l50mg/l00ml (0.15 percent by weight) or greater, concentrations that far exceed those attainable with usual social drinking. In order to reach 150mg/100ml, for example, a I55-lb. person, drinking between 1 and 2 hours after an average meal, would have to consume about 10 oz. of 80 proof liquor.

Survey of U.S. drivers about marijuana, alcohol, and driving

Objective: The primary goals were to gauge current opinions and behaviors related to driving after using marijuana and driving after drinking alcohol, and to examine how these responses vary by state laws on marijuana.

Methods: During July-October 2015, drivers 18 and older completed telephone interviews about their opinions on marijuana, alcohol, and driving, and their marijuana and alcohol use and driving. The study included representative samples of 1,508 drivers in three states with legalized marijuana for recreational use (Colorado, Oregon, and Washington), 2,510 drivers in five comparison states without legalized marijuana for recreational use (Idaho, Montana, Nebraska, Utah, and Wyoming), and 507 drivers in other states and the District of Columbia.

Results: Drivers were more likely to say that drinking and driving is a problem in their community than driving after using marijuana (64% vs. 29%). Drivers were more likely to agree that drinking and driving, relative to driving after using marijuana, is common in the community (56% vs. 34%) and increases the likelihood of a crash (98% vs. 78%). Reported alcohol use (57%) was far more prevalent than marijuana use (9%) within the past year. Drivers in states with legal recreational marijuana, relative to those in comparison states, more often said driving after using marijuana is a problem (43% vs. 28%), were twice as likely to report using marijuana within the past year (16% vs. 8%), more often were drinkers (60% vs. 46%), and more often had driven within 2 hours of using marijuana (6% vs. 3%) or drinking (21% vs. 15%).

Conclusions: Driving after drinking remains a bigger concern for the public than driving after using marijuana. However, this gap may narrow as states implement laws legalizing marijuana for recreational use. This survey can serve as a baseline for monitoring changes over time.

U.S. trends in late-night weekend alcohol-related fatal crashes and drinking and driving

Background: The proportion of U.S. drivers in fatal crashes with blood alcohol concentrations (BACs) of 0.08% or higher declined substantially from 1982 through the mid-1990s but changed little since, whereas periodic national roadside surveys reported large declines in alcohol use.

Aims: To examine possible explanations for the apparent disconnect between trends in drinking and driving and trends in the proportion of drivers with BACs =0.08% in fatal crashes.

Methods: The study looked at data from national roadside surveys conducted on Friday and Saturday late nights (10 p.m.-3 a.m.) in 1986, 1996, and 2007 and data on fatal crashes for these times and years. Differences in the roadside survey samples and protocols were examined, as were trends in rates of BACs =0.08% among driver sub-groups in the roadside surveys and FARS.

Results: Even after adjustments to the roadside surveys for differences in sampling and weighting, there were large declines in drivers with BACs =0.08% (5.4% in 1986, 4.2% in 1996, 2.6% in 2007) not reflected in rates of drivers with BACs =0.08% in fatal crashes (55.3% in 1986, 52.1% in 1996, 49.7% in 2007). Drivers with BACs =0.08% in fatal crashes were more likely than other drivers to drive older vehicles, be speeding, be unrestrained, and have prior moving violations and crashes/suspensions. Except for belt use, the differences were fairly consistent over time. Belt use increased more slowly among drivers with BACs =0.08%.

Conclusions: Different methodologies of roadside surveys do not appear to explain why alcohol impairment in fatal crashes has declined much less than the rate of drinking drivers in general. Trends generally were similar for sub-groups of drivers in roadside surveys and in fatal crashes. The fact that drinking drivers have been slower to buckle up appears to account for some of the discrepancy in trends, but there also appear to be other unknown factors.

Hardcore drinking drivers and other contributors to the alcohol-impaired driving problem: need for a comprehensive approach

Objective: Understanding the hardcore drinking driver concept in the context of the alcohol-impaired driving problem.

Method: Review of the relevant literature.

Results: As progress against alcohol-impaired driving slowed in the early 1990s, public and political attention turned to "hardcore" drinking drivers, and they have been a priority for the past 15 years. Though intuitive, the hardcore concept has been difficult to conceptualize. Its definition of hard-to-change chronic heavy drinking drivers focuses on a group that is not easily identifiable and ignores many who account for a large portion of alcohol-impaired driving crashes. These include drivers who drink heavily on occasion and drivers who drink at more moderate levels that elevate crash risk. Emphasis on the hardcore has focused attention on the small proportion of drinking drivers who have been detected and arrested, whereas the vast majority of drinking drivers go undetected. Some countermeasures aimed at the hardcore group have been effective in reducing recidivism, but attention and resources also need to be given to general deterrent initiatives (e.g., 0.08 g/dL, sobriety checkpoints, administrative license suspension). There has been no reduction in the overall alcohol-impaired driving problem since the mid-1990s.

Conclusion: Reductions in the alcohol-impaired driving problem require that attention be focused on all relevant target groups. Some benefits could accrue by recognizing that countermeasures developed for hardcore drinking drivers, such as alcohol ignition interlocks and vehicle or plate impoundment, might also be effective with more numerous first-time offenders. However, such strategies are likely to be most effective against recidivism (specific deterrence). Greater gains could be achieved through general deterrent efforts (increasing the real and perceived risk of arrest and punishment to all drinking drivers), along with application of public health measures designed to reduce overall consumption. Additional ways need to be found to separate drinking and driving, either through cultural changes in drinking and/or driving behavior or, in the future, with the use of technology that can make vehicles inoperable by drivers with illegal blood alcohol concentrations.

Drinking and driving among Mexican American and non-Hispanic white males in Long Beach, California

Although drinking and driving in the United States has declined substantially during the past two decades, this trend has not been seen among Hispanic drivers. Higher rates of driving while impaired (DWI) arrests and alcohol-related crashes, particularly among Mexican Americans, also have been noted. The extent to which this reflects a lack of understanding of DWI laws rather than a disregard for them is unknown. A survey was conducted among Mexican American and non-Hispanic white male DWI arrestees in Long Beach, California, to ascertain alcohol use, attitudes toward drinking and drinking and driving, and knowledge of DWI laws. The findings were compared with those of Mexican American and non-Hispanic white males recruited from the local community. Mexican American males, both DWIs and those from the community, reported heavier drinking than non-Hispanic white males. All four groups of respondents tended to underestimate the number of drinks needed to achieve the blood alcohol concentration (BAC) threshold at or above which it is illegal to drive under California law. Estimations were around 2-3 drinks rather than a more realistic estimate of 4-5 drinks. However, Mexican American DWIs and their comparison group vastly overestimated the number of drinks to make them unsafe drivers (8- 10 drinks). Furthermore, fewer than half were aware of the BAC threshold in California (0.08%) compared with between 60 and 78% of non-Hispanic whites. This study is limited in scope and needs to be replicated in other communities and with other racial/ethnic groups. However, the clear lack of knowledge of the DWI law in California and a lack of understanding of the relationship between number of drinks and BAC point to the need for culturally sensitive programs that are developed and implemented within the Mexican American community.

Research needs and priorities in alcohol-impaired driving among special populations

Ferguson, Susan A.Transportation Research Circular 502 Alcohol and Other Drugs in Transportation: Research Needs and Priorities January 2001

Abstract

The focus of this paper is to examine the research needs among alcohol-impaired special populations, including women versus men, different racial/ethnic groups, and people living in rural versus urban locations. The research proposals presented are aimed at lessening the gap in understanding of drinking and driving among special populations with the ultimate goal being to devise appropriate countermeasures.

Seat belt use and alcohol-impaired driving: behavior and attitudes in Australia, Canada, the United Kingdom, and the United States

The highway safety problem has similar dimensions in all motorized societies. Two factors that have contributed strongly to motor injuries worldwide are alcohol-impaired driving and failure to use seat belts. While all countries have made substantial efforts to decrease alcohol-impaired driving and increase belt use rates, they have taken somewhat different paths in addressing these common problems, and some have done better than others. Countries such as Australia have achieved remarkable gains in both areas, while other countries have lagged. The United States is a laggard particularly in the belt use area. It may be possible for less successful countries to learn from others how to make greater progress toward their goals. To investigate this possibility, a telephone survey of drivers in four countries was undertaken. This survey obtained information on drivers’ self-reported behavior regarding seat belt use and drinking and driving as well as their attitudes and perceptions about these behaviors and the laws governing them. There are two separate existing publications that present and discuss the survey results [1,2]. This paper summarizes and comments further on information in the prior reports.

Self-reported drinking and driving practices and attitudes in four countries and perceptions of enforcement

A telephone survey of 2,251 drivers was conducted to compare self-reported behavior and attitudes regarding alcohol consumption and driving in the United States with Australia, Canada, and the United Kingdom. U.S. respondents were less likely to say they drank and reportedly drank smaller quantities than respondents in Australia, Canada, and the United Kingdom. Drivers were most likely to have been checked for alcohol in Australia (82%). Respondents supported tough penalties; 45%-60% thought current penalties were not tough enough. Forty two percent in the United States, 26% in Australia, 35% in Canada, and 47% in the United Kingdom thought police were not doing enough enforcement. Results indicate that there is public tolerance for vigorous enforcement of tough laws and that increased enforcement in the United States and elsewhere would be an acceptable means of addressing the problem of alcohol-impaired driving.

Drunk driving among American Blacks and Hispanics

This paper reports the results of a literature search to determine the extent and nature of minority group involvement in drunk driving. Most of the research supports the view that American blacks and Hispanics are disproportionately more likely to be drunk drivers. However, the evidence is not fully consistent. The general relationship seems to be reduced or even reversed for minority youth. Furthermore, studies based on self-reported behavior contradict those based on official statistics such as alcohol-related deaths, traffic arrests, and accidents. Self reports generally show less drunk driving among the minority groups.

Blood alcohol levels in drivers not involved in accidents and the lognormal distribution

Recent conclusions by Smart and Schmidt [abst. in Quart. J. Stud. Alc. 31:1048, 1970], concerning the proportion of impaired drivers in nonaccident-involved populations, were based on an incorrect property of the lognormal distribution; there can be an infinite number of lognormal curves with the same mean but different proportions above some specified value of the variable. The distribution of blood alcohol concentrations (BACS) from one group of nonaccident drivers is significantly different from the best fitting two-parameter lognormal distribution. Reducing the mean of all drivers' BACS will not necessarily reduce the proportion of drivers with high BACS.

Survey of U.S. drivers about marijuana, alcohol, and driving

Objective: The primary goals were to gauge current opinions and behaviors related to driving after using marijuana and driving after drinking alcohol, and to examine how these responses vary by state laws on marijuana.

Methods: During July-October 2015, drivers 18 and older completed telephone interviews about their opinions on marijuana, alcohol, and driving, and their marijuana and alcohol use and driving. The study included representative samples of 1,508 drivers in three states with legalized marijuana for recreational use (Colorado, Oregon, and Washington), 2,510 drivers in five comparison states without legalized marijuana for recreational use (Idaho, Montana, Nebraska, Utah, and Wyoming), and 507 drivers in other states and the District of Columbia.

Results: Drivers were more likely to say that drinking and driving is a problem in their community than driving after using marijuana (64% vs. 29%). Drivers were more likely to agree that drinking and driving, relative to driving after using marijuana, is common in the community (56% vs. 34%) and increases the likelihood of a crash (98% vs. 78%). Reported alcohol use (57%) was far more prevalent than marijuana use (9%) within the past year. Drivers in states with legal recreational marijuana, relative to those in comparison states, more often said driving after using marijuana is a problem (43% vs. 28%), were twice as likely to report using marijuana within the past year (16% vs. 8%), more often were drinkers (60% vs. 46%), and more often had driven within 2 hours of using marijuana (6% vs. 3%) or drinking (21% vs. 15%).

Conclusions: Driving after drinking remains a bigger concern for the public than driving after using marijuana. However, this gap may narrow as states implement laws legalizing marijuana for recreational use. This survey can serve as a baseline for monitoring changes over time.

Role of cannabis and benzodiazepines in motor vehicle crashes

Alcohol is known to increase crash risk, but the evidence for other drugs is much less clear. Studies have been hampered by measurement issues and the small proportions of drivers found with drugs other than alcohol, especially drugs in the absence of alcohol. Cannabis and benzodiazepines (BZDs) are the two drugs other than alcohol most often found among crash-involved drivers. Both have been found to impair driving skills measured in the laboratory, but there are few adequate studies assessing their contribution to crashes, and these studies have mixed results. The weight of the evidence suggests that BZDs increase crash risk, in particular long-acting BZDs prescribed for medical use, at least for the first weeks of use. Further studies of cannabis and BZDs are needed to clarify their contribution to the highway safety problem.

Comments on "Evidence of alcohol and drug impairment obtained after arrest"

Evidence of alcohol or drug impairment is an essential element of a criminal prosecution for driving while impaired (DWI) by alcohol or drugs. Such evidence, or the refusal to provide such evidence, also is essential in the administrative license sanction area. Evidence of impairment includes: (1) Chemical testing for alcohol or drugs (obtaining and analyzing blood, breath, or urine samples); (2) Observations of the driver including (a) physical condition, appearance, and behavior and (b) physiological and behavioral tests indicating possible impairment; and (3) Statements by the driver admitting alcohol and or drug consumption and impairment. Chemical testing for the presence and amount of alcohol or drugs in a driver's body is the most important type of evidence of impairment. However, when a driver refuses to provide such evidence, the prosecution of an individual for DWI is often limited to the other types of impairment evidence listed above. This paper discusses post-arrest impediments to obtaining evidence of impairment of a driver arrested for DWI, the dynamics and incidence of chemical test refusal, procedures for reducing the refusal rate or reducing the effectiveness of refusal in preventing a conviction for DWI, and the problems and possible solutions to the issue of obtaining chemical tests for impairment from injured drivers receiving treatment at emergency medical facilities after involvement in motor vehicle crashes.

Issues and methods in the detection of alcohol and other drugs

The central question of this workshop is: How can it reliably be established that a person has consumed alcohol and/or other drugs in amounts that are illegal and/or may cause harm to that person or others? Many people think of this as a relatively easy task, conjuring up images of the “falling down drunk,” although even this obvious display may be something else, for example, diabetic shock. The reality is that even when people have high blood alcohol concentrations (BAC) known to cause signi cant impairment, it can be difficult for experts and laypersons alike to detect alcohol, especially among seasoned users and among people who wish to remain undetected. Detecting drugs other than alcohol presents its own set of problems, and in many cases the behavioral cues are less obvious than when alcohol has been consumed. The workshop’s focus is on police detection of alcohol and other drugs among drivers of private motor vehicles.

Drug use by tractor-trailer drivers

Blood or urine samples or both were obtained from 317 of 359 randomly selected tractor-trailer drivers asked to participate in a driver health survey conducted at a truck weighing station on Interstate 40 in Tennessee. Altogether, 29% of the drivers had evidence of alcohol, marijuana, cocaine, prescription or nonprescription stimulants, or some combination of these, in either blood or urine. Cannabinoids were found in 15% of the drivers' blood or urine; nonprescription stimulants such as phenylpropanolamine were found in 12%; prescription stimulants such as amphetamine were found in 5%; cocaine metabolites were found in 2%; and alcohol was found in less than 1%. These results provide the first objective information about the use of potentially abusive drugs by tractor-trailer drivers. The extent of driver impairment attributable to the observed drugs is uncertain because of the complex relationship between performance and drug concentrations.

Drugs in fatally injured young male drivers

One or more drugs were detected in 81 percent of 440 male drivers, aged 15-34, killed in motor vehicle crashes in California; two or more drugs were detected in 43 percent. Alcohol, the most frequently found drug, was detected in 70 percent of the drivers, marijuana in 37 percent, and cocaine in 11 percent. Each of 24 other drugs was detected in fewer than 5 percent. Except for alcohol, drugs were infrequently found alone; typically, they were found in combination with high blood alcohol concentrations. The causal role of drugs in crashes was assessed by comparing drivers with and without drugs in terms of their responsibility for the crash. Alcohol was associated with increased crash responsibility; the role of other drugs could not be adequately determined.

Profiles of tetrahydrocannabinol metabolites in urine of marihuana users: preliminary observations by high performance liquid chromatography-radioimmunoassay

Metabolic profiles of 11-nor-9-carboxylic acid-delta 9-tetrahydrocannabinol (COOH-THC) and other THC metabolites were determined in an infrequent and a frequent marijuana user by high performance liquid chromatography-radioimmunoassay (HPLC-RIA). In the infrequent user, no unconjugated COOH-THC was detected in urine samples for the first 8 h following smoking, whereas this metabolite was detected in the urine samples from a frequent user. A metabolite was also detected in the frequent user, which was not present in the urine sample from the infrequent user.

The disposition of tetrahydrocannabinol, 11-hydroxy-tetrahydrocannabinol and 11-nor-9-carboxylic acid tetrahydrocan in frequent and infrequent marijuana users

Peat, Michael A.Insurance Institute for Highway Safety 1985

Abstract

Plasma concentrations of THC, OH-THC and COOH-THC were measured after frequent and infrequent marijuana users smoked a single marijuana cigarette containing 1.8% THC. Plasma THC concentrations of greater than 1 ng/ml were detected for at least six hours in frequent users compared to two hours in infrequent users and COOH-THC concentrations of greater than 10 ng/ml were measured for at least six days in frequent uers. For THC t1/2 a2 was significantly longer in frequent users when compared to infrequent users. Pre-smoking plasma concentrations of THC and COOH-THC ranged from 0.4 to 1.6 ng/ml and from 11 to 83 ng/ml respectively in frequent users. Of the COOH-THC excreted in the urine over fourteen days, 51% was excreted in the first 24 hrs in infrequent users and 49% in frequent users. THC was detected in saliva samples from frequent users for at least 8 hrs. From our study the use of dispositional data to estimate the time of last smoking would be unreliable unless an accurate drug history of the subjects i s known.

Automobile injuries related to drug abuse: an introduction to some of the basic considerations in prevention and research

Haddon, William Jr.Public Health Reports May/June 1984

Abstract

The paper holds that research and preventive measures to reduce injuries stemming from the use of alcohol and other drugs in relation to motor vehicles need not always be concerned with the pharmacologic agents in crash initiation and with the characteristics of their users. It would be more constructive from the standpoint of reducing injuries to give more emphasis to those characteristics of these events whose practical modification would ameliorate or completely prevent the final result, injury of given severity. The author presents a matrix to sort out the pieces of comprehensive data collection, research, preventive or other approach to losses associated with vehicle use. The matrix also points out where alcohol and other drugs fit in the overall picture. In this matrix, the general sequence of events which lead to given totals of losses on public or private balance sheets divides into three phases of interactions which are labelled PreEvent, Event, and PostEvent. The use of the matrix and the method is discussed.

The stabilities of delta 9-tetrahydrocannabinol (THC) and two of its metabolites, 11-hydroxy-delta 9-tetrahydrocannabinol (HO-THC) and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (COOH-THC), were determined in blood and plasma stored at -10 degrees C, 4 degrees C, and room temperature. Each of the cannabinoids was added to freshly-drawn blood and plasma to give concentrations of 20 ng/mL. Two-mL aliquots were stored in silanized tubes and the cannabinoid concentrations were monitored by gas chromatography/mass spectrometry over a 6-month period. No significant changes were observed in the concentrations of the cannabinoids for the first month of storage. However, the concentrations of THC and HO-THC in blood stored at room temperature had decreased significantly at 2 months. No statistically significant changes were detected in cannabinoid concentrations in plasma or blood stored at 4 degrees or -10 degrees C for up to 4 months. After 6 months at room temperature, the blood concentrations of THC and HO-THC had decreased by 90 and 44%, respectively, whereas the concentration of COOH-THC was not significantly different from the control. The possibility of loss of cannabinoids from blood due to adsorption onto the grey stoppers used in Venoject tubes was also investigated. Over a 24-hr period, no significant differences were detected in any of the cannabinoid concentrations regardless of sample size (1.3 or 8 mL), differences in temperature (-10 degrees C, 4 degrees C, or room temperature), or extent of contact with the tube's stoppers.

Drugs and driving: a systematic analytical approach

To collect useful epidemiological data about drug involvement in highway safety, it is essential that sensitive and specific analytical procedures be used to establish the presence of and to determine the concentrations of drugs and metabolites in samples collected from drivers. This paper describes a comprehensive and systematic screening procedure requiring 6 mL of blood, which has been used for the analysis of samples collected from injured and fatally injured drivers. The procedure uses radioimmunoassay, gas chromatography with selective detectors, and high performance liquid chromatography. Drugs and metabolites presumptively identified are then confirmed primarily using gas chromatography--chemical ionization mass spectrometry.

Recent trends in fatal poisoning by opiates in the United States

Deaths in the United States classified as unintentional poisoning by drugs and medicaments fell from 14.7 per million population in 1975 to 8.8 in 1978, a 40 per cent decrease. Seventy-three per cent of this drop attributable to a reduction in deaths coded to opiates and intravenous narcotism. These two categories accounted for 38 per cent of all unintentional drug deaths in 1975 but only 15 per cent in 1978. There was no simultaneous increase in other drug-related deaths, including suicides, to account for the reduction in deaths coded to opiates. The highest mortality rates and the greatest variation in mortality during 1970-78 occurred in 20-29 year old non-White males. Racial and sex differences in opiate poisoning mortality, notable early in the decade, were greatly reduced by 1978 due to a relatively larger decline in mortality of males and non-Whites. Time trends in mortality from opiate poisoning appear to coincide with variations in the amount of heroin smuggled into the country.

delta 9-Tetrahydrocannabinol and two of its metabolites, 11-hydroxy-delta 9-tetrahydrocannabinol and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol, can be measured in a single 1-ml sample of blood, plasma, or urine by a new assay which combines a relatively rapid extraction procedure with capillary column gas chromatography and negative ion chemical ionization mass spectrometry. Deuterium-labeled analogs of each cannabinoid are added to the physiological specimen as internal standards. Two extracts are obtained from each sample: a neutral fraction containing delta 9-tetrahydrocannabinol and 11-hydroxy-delta 9-tetrahydrocannabinol, and an acid fraction containing 11-nor-9-carboxy-delta 9-tetrahydrocannabinol. The neutral fraction is derivatized by treatment with trifluoroacetic anhydride; the acid fraction is first treated with BF3-methanol followed by reaction with trifluoroacetic anhydride. Under electron-capture chemical ionization conditions the derivatized delta 9-tetrahydrocannabinol and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol give abundant molecular anions ideally suited for selected ion monitoring. The negative ion chemical ionization spectrum of the HO-THC-trifluoroacetate shows no molecular anion. Consequently, quantitation of the hydroxy metabolite is achieved by monitoring a fragment ion formed by loss of CF3CO2 from its molecular anion. The limits of reliable measurement are judged to be 0.1 ng ml-1 for 11-nor-9-carboxy-delta 9-tetrahydrocannabinol, 0.2 ng ml-1 for delta 9-tetrahydrocannabinol and 0.5 ng ml-1 for 11-hydroxy-delta 9-tetrahydrocannabinol. Four examples are given of the application of the assay to the analysis of specimens of medico-legal importance.

Alcohol, marihuana and skills performance

There now exists a large body of studies which demonstrate that the ingestion of either alcohol or mairhuana will produce decrements in the performance of skills which are important for man-machine interactions such as driving. In light of evidence of an increase in the combined use of these substances, attention currently is being given to the effects on driving related skills of alcohol and marihuana together. In a study by Manno et al. (1971) the combined alcohol and marihuana treatment produced greater impairment of pursuit tracking and mental arithmetic tasks than did either drug alone. Similarly, Macavoy and Marks (1975) reported increased impairment of visual signal detection under combined alcohol-marihuana treatment. In an extensive examination of this issue by Chesher and colleagues (Chesher et al., 1976, 1977; Belgrave, 1979) combined drug treatments were examined with a test battery which included standing steadiness, pursuit rotor, reaction time, and arithmetic and language tasks. The results were highly dependent on the task under examination. Under the combined treatment most of the psychomotor tasks showed a roughly additive increase in impairment over the effects of the single treatments. On the other hand, performance of the cognitive tasks was not more impaired by the combined treatment than by marihuana alone, but the effect was greater than for alcohol alone. In the current study, a test battery, including skills performance tasks and cognitive tasks, was examined under the single and combined treatments of 0.58 g alcohol/kg bodyweight. The marihuana and the alcohol treatment levels are typical of amounts commonly used by moderate users of alcohol and moderately heavy users of marihuana.

A new GC/MS assay has been developed for quantitation of THC in phsyiological specimens. The method involves formation of the trifluoroacetyl derivative of THC and use of electron capture negative ion chemical ionization. The sensitivity of the assay is at least ten times greater than methods based upon positive ion chemical ionization or electron impact ionization. Furthermore, the negative ion CI method is more selective so that there is less interference from other components of biological extracts. The method can also be used for quantitation of the 9-carboxy metabolite of THC by modification of the extraction procedure and use of a two-stage derivatization involving methylation with diazomethane followed by acetylation with trifluoroacetic anhydride. The negative ion CI mass spectra of the trifluoracetyl derivatives of THC and the methyl ester of the 9-carboxy metabolite show intense molecular anions with no abundant fragment ions, even at ion source temperatures up to 200 degrees C.

GC/MS assays for abused drugs in body fluids

This monograph presents a collection of methods for the quantitative analysis of several important drugs of abuse by the technique of gas chromatography-mass spectrometry (GC/MS). The material is arranged textbook fashion, by chapters on specific drugs, to assist researchers in setting up GC/MS assay procedures in their own laboratories. These assays are particularly suited to basic studies on the pharmacology and pharmacokinetics of drugs of abuse. Forensic toxicology, which sometimes requires the highly sensitive and specific sample analysis provided by GC/MS, is another important area of application. Even when an alternate method such as immunoassay is available for such analyses, GC/MS is often the only means of providing a confirmation assay. The sensitivity and specificity of GC/MS are especially critical to studies on the impact of drugs on traffic safety. In addition, demand for legislation relating to drugs and highway safety is increasing, and enforcement of such laws will necessitate appropriate sample assays. The unique characteristics of the GC/MS analytical method make it the only means of determining drug levels under certain circumstances. The inherent complexity of the technique, however, often dissuades investigators from embarking on studies that involve its use. At a time when basic questions underlying drug abuse call for increasingly sophisticated methods of data acquisition this monograph should provide the information needed to make one of these procedures easier to establish and to encourage new areas of research.

Effects of diphenhydramine and alcohol on skills performance

Twelve men were subjects in a repeated measures experiment on the effects on performance of diphenhydramine, alcohol, and diphenhydramine and alcohol in combination. Behavioral measures included compensatory tracking, a divided attention task, information processing rate, and critical tracking. Performance impairment occurred under all treatments with an additive effect under the combined drug-alcohol treatment.

Effects of diazepam and alcohol on skills performance

Performance scores for all tasks in a behavioral test battery were lower under diazepam than under placebo. The diazepam dose of .0726 mg/kg bodyweight significantly impaired an information processing task and tracking performance under divided attention conditions. An aclohol dose of 0.58 gm/kg bodyweight significantly impaired performance of all response measures. The combined diazepam-alcohol treatment produced greater performance decrements than either treatment alone. Moderate doses of diazepam and alcohol, alone and in combination impaired performance on a battery of tests which represent the skills requirements of driving.

Detection of tetrahydrocannabinol in blood and serum using a fluorescent derivative and thin-layer chromatography

A thin-layer chromatographic method is described for the detection of delta-9-tetrahydrocannabinol in blood and serum. The procedure utilizes a reagent, 2-p-chrlorosulfophenyl-3-phenylindone, which reacts with the phenolic group to form a derivative. Following extraction and cleanup, the derivative is prepared and separated from reagent and naturally occurring compounds by thin-layer chromatography. The derivative is then detected by spraying the thin-layer plate with an alkoxide spray which produces a fluorescent spot visible under long wave ultraviolet light. The method can detect 0.2 ng/ml of tetrahydrocannabinol in 5 ml of serum and is suitable for routine screening.

The effects of alcohol and valium, singly and in combination, upon driving-related skills performance

Moskowitz, Herbert A.; Burns, Marcelline M.Proceedings of the 21st Annual Conference of the American Association for Automotive Medicine 1977

Abstract

Twelve male participants, ages 21-42, were tested in four laboratory sessions under diazepam alone, alcohol alone, diazepam and alcohol in combination, and placebos. The test battery included pursuit tracking, visual divided attention, and visual backward masking. Performance deficits were found under the separate treatments, with an additive effect under the combined alcohol-diazepam treatment.

Information processing was tested in 12 male subjects after smoking marihuana containing 0, 10, or 20 mg. of delta-9-tetrahydrocannabinol (THC) in three consecutive experimental sessions according to a Latin square protocol. Successful dose control was indicated both by the dose-related linear increase observed in heart rate and by preliminary assays of THC metabolites excreted in the urine. During tachistoscopic presentation of varying numbers of circles, statistically significant decrements in information processing occurred as a function of THC dosage. However, adding irrelevant information (triangles) to the display of circles eliminated effects of marihuana on accuracy of counting. Complex reaction times for oddity discrimination increased significantly only after the high dose. Nonetheless, both the social and high doses inappropriately inhibited the general tendency to respond to changing stimuli during oddity discrimination. Marihuana had no effect on field-dependence as measured by the Rod-and-frame test.

Excretion of urinary cannabinoids after marihuana smoking (abstract)

Urinary cannabinoids were measured by homogeneous enzyme iamunoassay in 12 healthy, adult males before and after administration of 0.5(placebo), 10, and 19.8 mg of THC by marihuana smoking, to determine whether and for how long prior marihuana smoking was detectable. TCH uptake was confirmed by linear heart-rate increases during and after smoking. Urine was collected in 6-hr. aliquots for 4+ days. Results of cannabinoids assay were normalized for urine creatinine concentration measured by an automated Jaffe method.

Detection and quantitation of tetrahydrocannabinol in serum

Much research is being performed in the cannabinoid field due to the increasing concern over the use of marijuana among the youth of America and Western Europe. The purpose of this work was to establish a sensitive analytical method for determining THC (active componenet of marijuana) in physiological fluids. Tetrahydrocannabinol occurs in plasma in very low concentrations (3-50 ng/ml) with the peak level starting to decrease ten minutes after smoking. The physiological effects are most evident for a period of two to three hours after smoking. The level of plasma after two hours is about 3 ng/ml cubed. Thus a mehtod is needed which is capable of detecting THC down to 1 ng/ml. The method should be suitable for routine use, sensitive, specific, inexpensive and preferably amenable to quantitative analysis. There are several methods currently available for the detection of an analysis of THC including Electron-capture gas chromatography, Mass spectrocopy, Mass fragmentography, gas chromatorgraphy + Mass spectrocopy, Radioimmunoassay, High pressure liquid chromatography and Thin layer chomatography (TLC). Among all of these TLC is the simplest and least expensive of the techniques and is thus suitable for routine use. However, a previous report using TLC for THC in urine has not been replicated. The basic problem with TLC is sensitivity. Dansyl derivatives of THC give fluorescent spots detectable at 0.5 ng but the spots are unstable to light thus limiting the utility. A TLC method will be described here which is suitable for routine use in the detection of THC in blood, serum or plasma using a new fluorescent derivatizing reagent DIS-CL.

Breath analysis as a technique in clinical chemistry

Dubowski, Kurt M.Clinical Chemistry August 1974

Abstract

Breath possesses unique advantages as a specimen for clinical chemical analyses, including the continuous equilibrium of gases and volatile substances between expired alveolar air and the pulmonary blood circulation. Substances amenable to analysis in breath include O2, CO2, CO, and other gases, volatile organic compounds, and many drugs with sufficiently high vapor pressures at physiological temperatures. Practical aspects of breath sampling and breath analysis are discussed, exemplified by breath-alcohol analysis. The requirements for obtaining breath samples in equilibrium with the pulmonary blood circulation are delineated, and experimental data are presented for the significant breath-sample characteristics bearing on design of breath collection and storage systems (end-expiratory temperature, breath volumes).

Marihuana and driving among teenagers: reported use patterns, effects, and experiences related to driving

Forty-nine per cent of 1271 incoming college freshmen reported using marihuana during the previous year. A majority of marihuana users simultaneously consume alcohol at least on occasion, and many of them have enough alcohol at those times to be impaired by the alcohol alone. Among users who smoke weekly or more often one-quarter of driving while “high” occurs under the combined effect of marihuana and medium to heavy alcohol use. Most users reported marihuana effects on driving judged to be hazardous, such as altered attention, vision or time perception. In an estimated 15,000 driving trips while “high” on marihuana two crashes occurred definitely attributable and two possibly attributable to marihuana use. Also, 42 persons (13 per cent of drivers) reported near crashes while “high”. Since this is not a comparison study, it is not known whether or not this reported experience is excessive for this age group. Drivers who encountered trouble while driving after marihuana said 59 per cent of the time that the incidents were caused by the marihuana, 27 per cent by alcohol, and in 14 per cent that they couldn't assess which drug was responsible.

Confirmation of the presence of 11-hydroxy-9-tetrahydrocannabinol in the urine of marihuana smokers

Woodhouse, Edward J.American Journal of Public Health 1972

Abstract

The presence of 11-hydroxy- A 9-tetrahydrocannabinol has been identified and confirmed in the urine of marijuana smokers. The analytical methods involved are liquid extraction by organic solvents followed by thin-layer chromatography and mass spectrometry of the thin-layer eluates. The presence of other cannabinoid metabolites is also indicated.

Detection of marihuana components in urine (3375-C)

Woodhouse, Edward J.Insurance Institute for Highway Safety March 1971

Abstract

The objective of this program was to develop a field method for the identification of marhuana smokers. The best color reagents for the detection of marihuana in urine are described. Laboratory and field tests using finger dips and swabs, mouth washes and swabs, and urine specimens have been investigated. Conclusions are presented on th applicability of these tests in identifying marihuana smokers, and recommendations for future research are detailed.

The North Carolina Governor's Highway Safety Initiative: initial results from "Booze It and Lose It"

The North Carolina Governor's Highway Safety Initiative is a multiyear program intended to reduce motor vehicle crashes and injuries through publicity/enforcement programs aimed at increasing seat belt use, reducing alcohol-impaired driving, and reducing high speed driving. In 1993-94, a two-stage statewide program involving 6,364 seat belt checkpoints and 58,883 citations increased seat belt use to over 80 percent. The first round of a similarly intensive program addressing alcohol-impaired driving is being launched in November 1994. It features a three-week statewide program of heavy enforcement with checkpoints and roving saturation patrols and extensive publicity about the enforcement. Four emphasis areas - cities or counties within the state - are receiving additional treatment. Pre- and post-program on-the-road surveys of drinking and driving, and before and after telephone surveys are being used to measure the initial effects of the alcohol program. This paper describes the development and evolution of the Governor's Highway Safety Initiative, the alcohol program, and survey results documenting the effects of the first of several anticipated cycles of concentrated, highly publicized enforcement.

The contribution of education and public information to reducing alcohol-impaired driving

Williams, Allan F.Alcohol, Drugs, and Driving 1994

Abstract

Laws aimed at alcohol-impaired driving have been shown to change behavior in ways that reduce the problem. Alcohol education and public information programs, in contrast, rarely result in short-term behavior change. In part, this is because drinking, and combining drinking with driving, are lifestyle behaviors shaped and supported by many ongoing social forces, and they are not readily amenable to change through brief, one-time education/public information efforts. Moreover, those who contribute most to the problem have characteristics that make them least susceptible to behavior change through educational programs. However, education and public information programs have an important role to play in combating alcohol-impaired driving. They can provide support and impetus for passing laws; transmit knowledge about the provisions and penalties of laws in ways that increase their deterrent effect; and generate public support for law enforcement programs. Greater attention to educating and informing policy and decision makers, rather than at-risk individuals, is needed.

Confronting drunk driving: social policy for saving lives

Ross, H. LaurenceInsurance Institute for Highway Safety 1992

Abstract

In this controversial book, a noted authority argues that drunk driving cannot be controlled by punishments administered through the criminal justice system alone. Instead, H. Laurence Ross offers a range of practical solutions to the problem, combining criminal deterrence with suggestions that could reduce alcohol use, lessen automobile use in situations involving drinking, and improve automobile safety.

Evaluation of community programs

Robertson, Leon S.Proceedings of the 7th International Conference on Alcohol, Drugs and Traffic Safety 1979

Abstract

In those countries where careful analysis of the concentration of alcohol in the body fluids of appropriate series of dead drivers and pedestrians has been done, the frequency of alcohol and its high concentration is substantial. The relative lack of alcohol in drivers and pedestrians observed at the same places, at the same times and moving in the same direction as the fatally injured clearly implicates alcohol as a causal factor in the fatalities. As the involvement of alcohol in severe crashes became widely known, many people believed that it logically followed that community programs should and could reduce the alcohol consumption of drivers and pedestrians. If one examines alcohol's role in motor vehicle crashes within the context of the causes and amelioration of other public health problems, however, it does not logically follow that community programs should necessarily be undertaken to reduce alcohol consumption. Furthermore, the better designed evaluations of community programs attempting to reduce alcohol and drug consumption have' had, at best, temporary effects, often no effects, and some adverse effects. This paper examines the relationship between types of causation and choice of public health strategies, and compares the effectiveness of loss reduction programs focused on alcohol with other injury and disease reduction programs. It concludes with recommendations for selected community efforts based on sound logic and research.

A rejoinder to "A critique of the paper 'Statistical evaluation of the effectiveness of alcohol safety action programs' by Johnson et al."

Zador, Paul L.Accident Analysis and Prevention August 1977

Abstract

Criticisms by federal officials responsible for Alcohol Safety Action Projects claiming to invalidate the author's previous evaluation of the effectiveness of the Alcohol Safety Action Projects are discussed and are shown to be unfounded.

Statistical evaluation of the effectiveness of "alcohol safety action projects"

Zador, Paul L.Accident Analysis and Prevention 1976

Abstract

The programs were evaluated by comparing motor vehicle crash fatalities in a number of communities with such programs in similar communities with no programs. Program effectiveness was not found. Excessive use of alcohol is involved in more than one-half of all motor vehicle-related fatalities in the United States. In 1969 the department of transportation initiated a comprehensive program intended to reduce alcohol-related highway deaths and injuries. The most ambitious components of the program are the alcohol safety action projects (ASAPs), conducted at the community level. The major goals of the ASAPs are to demonstrate the feasibility and practicality of a systems approach for dealing with the drunk-driving problem and to demonstrate that this approach can save lives, to evaluate the individual countermeasures within the limits permitted by the simultaneous application of a number of different countermeasures at the same site, and to catalyze each state into action to improve its safety program in the area of alcohol safety. A total of 35 local ASAP have been started at an average cost of more than $2 million each. The active duration of an ASAP is 3 years. The design employed in this study evaluates ASAP effectiveness by comparing year-to-year variations in fatality statistics between groups of areas with ASAPs and comparison groups without ASAPs. The 28 ASAPs areas that are included in this study were examined in 13 groups--5 groups were formed from the 8 ASAPs that began in 1971 and 8 groups were formed from the 20 ASAPs that began in 1972. The basic statistic used in this analysis was a proportion, calculated by dividing the number of fatalities in each ASAP area in a year by the combined number of fatalities in the ASAP and comparison areas for that year. This proportion would not change systematically from year to year if changes in the ASAP and comparison area fatalities were comparable. Analysis results show that there is no evidence of a decline in the total number of fatalities in any of the communities examined that could be attributed to ASAP programs. In view of the results of the several detailed analyses presented in this paper, and in the absence of any evidence of an overall reduction in fatalities, it is only possible to conclude scientifically that ASAPs, as large scale social programs, have been ineffective.

Communications and public response to abusive drinking and highway crashes

Suggestions for educational programs about alcohol and highway safety

Waller, Julian A.Traffic Safety Research Review September 1968

Abstract

In this article, Dr. Waller presents some basic guidelines for the development of alcohol education programs based on currently available research data. A break-down of the groups to be reached by these programs is given and includes not only the drinking population but those who indirectly influence their behavior such as judges and driver licensing personnel, and those whose activities are directed to the reduction of death and injury such as physicians, police and legislators. The basic body of information which should be made available to the general public is outlined and, in addition, special information for each particular group is detailed.

McCartt, Anne T.; Eichelberger, Angela H.Proceedings of the 20th International Conference on Alcohol, Drugs, and Traffic Safety (CD-ROM) October 2013

Abstract

Background: Increasingly U.S. states mandate alcohol ignition interlock orders for all alcohol-impaired driving (DUI) convictions, but little research has examined their effects.

Aims: Examine effects on recidivism and alcohol-impaired crashes of Washington state’s ignition interlock laws, including a 2004 extension of the interlock requirement to all first DUI convictions and a 2009 law allowing interlocks in lieu of administrative license suspension; examine multi-state effects of interlock laws on alcohol-related fatal crashes.

Methods: Washington trends in conviction types and interlock installations for first DUI convictions were examined. Linear regressions examined recidivism rates with either law changes or interlock installation rates as predictors and all DUI arrests to control for enforcement variation. To examine general deterrence effects, times series cross-section regression was used to compare Washington single-vehicle late-night crash trends to California and Oregon trends and to examine effects of states’ interlock laws on alcohol-related fatal crash trends.

Results: After Washington’s 2004 law change, the interlock installation rate among affected offenders was about one-third compared to about 3-6% in the prior year. The 2-year recidivism rate declined 12% among affected offenders; a 0.06 percentage point decrease in recidivism was associated with each percentage point increase in the interlock use rate. The law change was associated with an 8% reduction in single-vehicle late-night crash risk. The 2009 law change appears to be having the desired effect of increasing interlock installations and ensuring they occur more quickly after arrest. Multi-state analysis of alcohol-related fatal crashes is underway.

Conclusions: Washington’s first-offender interlock laws were associated with reduced recidivism, even with low interlock use rates, and crash reductions. Additional gains may be achieved with higher interlock use rates, limiting reductions in DUI charges to other traffic offenses, and publicizing interlock laws.

Objective: To examine the effects of changes to Washington State’s ignition interlock laws: moving issuance of interlock orders from courts to the driver licensing department in July 2003 and extending the interlock order requirement to first-time offenders with blood alcohol concentrations (BACs) below 0.15 percent (“first simple driving under the influence [DUI]”) in June 2004.

Results: After the 2004 law change, the proportion of simple DUIs declined somewhat, though the proportion of negligent driving convictions (no interlock order requirement) continued an upward trend. Interlock installation rates for first simple DUIs were 3 to 6 percent in the year before the law change and one third after. Recidivism declined by an estimated 12 percent (e.g., expected 10.6% without law change vs. 9.3% among offenders arrested between April and June 2006, the last study quarter) among first simple DUI offenders and an estimated 11 percent (expected 10.2% vs. 9.1%) among all first-time offenders. There was an estimated 0.06 percentage point decrease in the recidivism rate for each percentage point increase in the proportion of first simple DUI offenders with interlocks. If installation rates had been 100 vs. 34 percent for first simple DUI offenders arrested between April and June 2006, and if the linear relationship between rates of recidivism and installations continued, recidivism could have been reduced from 9.3 to 5.3 percent. With installation rates of 100 vs. 24 percent for all first offenders, their recidivism rate could have fallen from 9.1 to 3.2 percent. Although installation rates increased somewhat after the 2003 law change, recidivism rates were not significantly affected, perhaps due to the short follow-up period before the 2004 law change. The 2004 law change was associated with an 8.3 percent reduction in single-vehicle late-night crash risk.

Conclusions: Mandating interlock orders for all first DUI convictions was associated with reductions in recidivism, even with low interlock use rates, and reductions in crashes. Additional gains are likely achievable with higher rates. Jurisdictions should seek to increase use rates and reconsider permitting reductions in DUI charges to other traffic offenses without interlock order requirements.

Attitudes toward in-vehicle advanced alcohol detection technology

Objectives: Efforts are underway to develop advanced alcohol detection technologies suitable for use in all vehicles to prevent driving with an illegal blood alcohol concentration (BAC). Attitudes toward having this technology in all vehicles were assessed.

Methods: A nationally representative sample of people 18 and older was interviewed by telephone.

Results: Eighty-four percent of survey respondents supported requiring alcohol ignition interlocks in the vehicles of convicted driving while intoxicated (DWI) offenders. Sixty-four percent said having advanced alcohol detection technology in all vehicles is a good or a very good idea, assuming the technology is reliable; 30 percent said it is a bad idea. Most people in favor said that it would prevent alcohol-impaired driving, save lives, or prevent crashes. Among respondents who said it is a bad/very bad idea, one third cited concerns about privacy or government interference; 20 percent said not all drivers need screening. Support was highest among respondents who do not drink, but it also was favored by the majority of respondents who drink, respondents who have driven within 2 hours of consuming alcohol, and respondents who may have driven when they were above the legal limit for alcohol. Forty-two percent of respondents who drive said they would want an advanced alcohol detection device in their next vehicles if it were available as an option at a reasonable price. Of the 54 percent who said they would not want a device, 44 percent said they do not drink alcohol so it would not be useful. Most people said a price less than $500 would be reasonable.

Conclusions: It appears that the majority of the U.S. population is receptive to the idea of having advanced alcohol detection devices in all vehicles to prevent people from driving with an illegal BAC, although less than half say they would purchase a device in their next vehicles.

Objectives: This investigation sought to test the effectiveness of a statewide ignition interlock license restriction program for drivers with multiple alcohol-related traffic offenses.

Methods: A total of 1387 multiple offenders eligible for license reinstatement were randomly assigned to participate in an ignition interlock program (experimental group) or in the conventional postlicensing treatment program (control group). The arrest rates of these 2 groups for alcohol traffic offenses were compared for 1 year during the ignition interlock license restriction program and for 1 year after unrestricted driving privileges were returned.

Results: Participation in the interlock program reduced offenders' risk of committing an alcohol traffic violation within the first year by about 65%. The alcohol traffic violation rate during the first year was significantly less for participants in the interlock program (2.4%) than for those in the control group (6.7%). However, there was no statistically significant difference between these groups in the second year, after the interlock license restriction was lifted.

Conclusions: Ignition interlock license restriction programs are effective at reducing recidivism among drivers with multiple alcohol offenses, at least while the restriction is in effect.

Objectives: This investigation sought to test the effectiveness of a statewide ignition interlock license restriction program for drivers with multiple alcohol-related traffic offenses.

Methods: A total of 1387 multiple offenders eligible for license reinstatement were randomly assigned to participate in an ignition interlock program (experimental group) or in the conventional postlicensing treatment program (control group). The arrest rates of these 2 groups for alcohol traffic offenses were compared for 1 year during the ignition interlock license restriction program and for 1 year after unrestricted driving privileges were returned.

Results: Participation in the interlock program reduced offenders' risk of committing an alcohol traffic violation within the first year by about 65%. The alcohol traffic violation rate during the first year was significantly less for participants in the interlock program (2.4%) than for those in the control group (6.7%). However, there was no statistically significant difference between these groups in the second year, after the interlock license restriction was lifted.

Conclusions: Ignition interlock license restriction programs are effective at reducing recidivism among drivers with multiple alcohol offenses, at least while the restriction is in effect.

Impaired driving enforcement practices among state and local law enforcement agencies in the United States

Introduction: Alcohol-impaired driving (DUI) persists as a substantial problem, yet detailed data on DUI enforcement practices are rarely collected. The present study surveyed state and local law enforcement agencies about their DUI enforcement activities.

Method: Telephone interviews were conducted with law enforcement liaisons in state highway safety offices. Officers from a nationally representative sample of municipal, county, and state law enforcement agencies were also interviewed about their agency's DUI enforcement activities, including the types of enforcement, frequency of use, and whether activities were publicized. Response rates were 100% among law enforcement liaisons, 86% among county agencies, 93% among municipal agencies, and 98% among state agencies.

Results: Based on the highway safety office survey, 38 states conducted sobriety checkpoints in 2011. Nationally, 58% of law enforcement agencies reported that they conducted or helped conduct sobriety checkpoints during 2011–12, with 14% of all agencies conducting them monthly or more frequently. The vast majority (87%) of agencies reported conducting dedicated DUI patrols. However, dedicated DUI patrols were less likely to be publicized than checkpoints. Less than a quarter of agencies reported using passive alcohol sensors to improve detection of alcohol-impaired drivers.

Conclusions: Results show that 38 states conducted sobriety checkpoints in 2011, little changed from a previous survey in 2000. Despite evidence of effectiveness, many agencies do not conduct frequent, publicized DUI enforcement or use passive alcohol sensors.

Practical applications: The survey suggests that there are several areas in which impaired driving enforcement could be improved: increasing the frequency of special enforcement, such as sobriety checkpoints and/or dedicated patrols; publicizing these efforts to maximize deterrent effects; and using passive alcohol sensors to improve detection of alcohol-impaired drivers.

McCartt, Anne T.; Eichelberger, Angela H.Proceedings of the 20th International Conference on Alcohol, Drugs, and Traffic Safety (CD-ROM) October 2013

Abstract

Background: Increasingly U.S. states mandate alcohol ignition interlock orders for all alcohol-impaired driving (DUI) convictions, but little research has examined their effects.

Aims: Examine effects on recidivism and alcohol-impaired crashes of Washington state’s ignition interlock laws, including a 2004 extension of the interlock requirement to all first DUI convictions and a 2009 law allowing interlocks in lieu of administrative license suspension; examine multi-state effects of interlock laws on alcohol-related fatal crashes.

Methods: Washington trends in conviction types and interlock installations for first DUI convictions were examined. Linear regressions examined recidivism rates with either law changes or interlock installation rates as predictors and all DUI arrests to control for enforcement variation. To examine general deterrence effects, times series cross-section regression was used to compare Washington single-vehicle late-night crash trends to California and Oregon trends and to examine effects of states’ interlock laws on alcohol-related fatal crash trends.

Results: After Washington’s 2004 law change, the interlock installation rate among affected offenders was about one-third compared to about 3-6% in the prior year. The 2-year recidivism rate declined 12% among affected offenders; a 0.06 percentage point decrease in recidivism was associated with each percentage point increase in the interlock use rate. The law change was associated with an 8% reduction in single-vehicle late-night crash risk. The 2009 law change appears to be having the desired effect of increasing interlock installations and ensuring they occur more quickly after arrest. Multi-state analysis of alcohol-related fatal crashes is underway.

Conclusions: Washington’s first-offender interlock laws were associated with reduced recidivism, even with low interlock use rates, and crash reductions. Additional gains may be achieved with higher interlock use rates, limiting reductions in DUI charges to other traffic offenses, and publicizing interlock laws.

Objective: To examine the effects of changes to Washington State’s ignition interlock laws: moving issuance of interlock orders from courts to the driver licensing department in July 2003 and extending the interlock order requirement to first-time offenders with blood alcohol concentrations (BACs) below 0.15 percent (“first simple driving under the influence [DUI]”) in June 2004.

Results: After the 2004 law change, the proportion of simple DUIs declined somewhat, though the proportion of negligent driving convictions (no interlock order requirement) continued an upward trend. Interlock installation rates for first simple DUIs were 3 to 6 percent in the year before the law change and one third after. Recidivism declined by an estimated 12 percent (e.g., expected 10.6% without law change vs. 9.3% among offenders arrested between April and June 2006, the last study quarter) among first simple DUI offenders and an estimated 11 percent (expected 10.2% vs. 9.1%) among all first-time offenders. There was an estimated 0.06 percentage point decrease in the recidivism rate for each percentage point increase in the proportion of first simple DUI offenders with interlocks. If installation rates had been 100 vs. 34 percent for first simple DUI offenders arrested between April and June 2006, and if the linear relationship between rates of recidivism and installations continued, recidivism could have been reduced from 9.3 to 5.3 percent. With installation rates of 100 vs. 24 percent for all first offenders, their recidivism rate could have fallen from 9.1 to 3.2 percent. Although installation rates increased somewhat after the 2003 law change, recidivism rates were not significantly affected, perhaps due to the short follow-up period before the 2004 law change. The 2004 law change was associated with an 8.3 percent reduction in single-vehicle late-night crash risk.

Conclusions: Mandating interlock orders for all first DUI convictions was associated with reductions in recidivism, even with low interlock use rates, and reductions in crashes. Additional gains are likely achievable with higher rates. Jurisdictions should seek to increase use rates and reconsider permitting reductions in DUI charges to other traffic offenses without interlock order requirements.

Objectives: The current study examined the relationship between court outcomes of a first alcohol-impaired driving charge and recidivism.

Methods: Data on arrests for alcohol-impaired driving offenses (driving under the influence [DUI] and the lesser offense of driving while impaired [DWI]) and associated court dispositions were obtained from the State of Maryland for 1994-2003. Drivers whose first DUI- or DWI-related disposition took place during 1999-2000 were included in analysis. Eighty-two percent of arrests resulted in conviction (29% without probation before judgment [PBJ] and 53% with PBJ); 10 percent of defendants were not prosecuted, 3 percent were acquitted, and all other adjudications combined (eg, abated by death, failure to appear) accounted for 5 percent. Recidivism was tracked by compiling instances of rearrest for an alcohol-related driving offense during the 3 years following disposition.

Results: Approximately 10 percent of all drivers arrested for DUI/DWI recidivated within 3 years after their first disposition, and the rate of recidivism varied by court outcome. The rate of recidivism was lowest (10%) for drivers who were convicted (with or without PBJ), followed by 13 percent for cases not prosecuted and 16 percent for acquittals. After controlling for other factors and relative to drivers who were acquitted, it was estimated that drivers who were not prosecuted were 23 percent less likely to recidivate, whereas drivers who were convicted with or without PBJ were 39 percent less likely to recidivate.

Conclusions: Data limitations prevented comparison of recidivism rates for convictions with and without PBJ. Reasons for not prosecuting are unknown, but the findings indicate that the decision is resulting in higher recidivism rates than would occur with prosecution and conviction.

Effects of enhanced sanctions for high-BAC DWI offenders on case dispositions and rates of recidivism

Implemented January 1, 1998, Minnesota's high-BAC law mandates more severe administrative pre-conviction penalties and more severe post-conviction penalties for offenses with BACs > or = 0.20%. Most notably, the law provides for the administrative impoundment of the license plate of first-time DWI offenders with BACs > or = 0.20. During the three years after the law took effect, a large majority of first-time and repeat offenders with BACs > or = 0.20% did, in fact, receive high-BAC administrative dispositions and/or high-BAC court convictions, which carried more severe penalties. For example, in 1998 85.6% of first offenders with BACs > or = 0.20% received a high-BAC administrative disposition and/or a high-BAC court conviction; 65.0% received both high-BAC administrative and high-BAC court dispositions. The proportion of high-BAC first-time offenders who received the statutory high-BAC dispositions declined from 1998 to 1999 and 2000. Based on survival analysis, the one-year recidivism rate among first offenders arrested in 1998 with BACs > or = 0.20% was significantly lower than for offenders with BACs 0.17-0.19% (who also had relatively high BACs but were not subject to enhanced sanctions), after controlling for age and gender. There were similar, but not significant, results for first offenders arrested in 1999.

Observational study of the extent of driving while suspended for alcohol impaired driving

A study was undertaken to determine the proportion of first-time alcohol-impaired driving offenders who drive while suspended and the circumstances and motivations for driving. Systematic, unobtrusive observations were conducted by surveillance professionals from Pinkerton Investigative Services, Inc., of first-time offenders in Milwaukee (WI) and Bergen County (NJ). Observations included two 4-hour periods during suspension (one weekday morning, one Friday/Saturday evening) and two 4-hour periods after license reinstatement (matched by day of week and time of day). In all, 1,000 hours of observational data were gathered for 93 subjects (57 in Milwaukee and 36 in Bergen County). Milwaukee subjects had more problematic driving histories and were significantly more likely to drive while suspended. Of subjects observed traveling in some way while suspended, 88% of Milwaukee subjects drove, compared to 36% of Bergen County subjects. Only 5% of Milwaukee subjects had their license reinstated, compared to 78% of Bergen County subjects. Bergen County subjects were significantly more likely to drive after reinstatement than during their suspension, suggesting that the suspension had an impact on the subjects driving patterns. Focus groups, conducted at both sites, indicated that the license suspension represented a much greater hardship for New Jersey offenders than for Milwaukee offenders. New Jersey laws are much stronger, and Bergen County offenders had a much higher perceived risk of apprehension and punishment for driving while suspended.

A study of DUI enforcement

Burns, Marcelline M.; Anderson, Ellen; Moio, JeneProceedings of the 16th International Conference on Alcohol, Drugs, and Traffic Safety December 2002

Abstract

The number of driving-under-the-influence of alcohol (DUI) arrests varies widely among traffic officers within the same agency. A study was undertaken in the State of Colorado to evaluate what factors might underlie such differences. Data were obtained by anonymous questionnaire from a sample of Colorado traffic officers who differed in their arrest rates. Differences in DUI arrest rates were not related to the officers’ personal experiences with alcohol, their knowledge about its effects, or their DUI enforcement training. The officers who made the most arrests generally were younger with fewer years in law enforcement and were more likely to say they actively seek DUI offenders, whereas those with low arrest numbers were more likely to say they arrest only those that they happen to see. Officers who made more arrests tended to have more positive attitudes about making DUI arrests and engage in a more active enforcement style. However these differences were small.

Comment on “Low BAC policies: results and mechanisms"

Ferguson, Susan A.Insurance Institute for Highway Safety 2001

Abstract

The questions we are being asked to address are as follows: What have been the results of lowering BAC limits for the general driving public? For specific populations? What are the likely mechanisms by which these results have been achieved? One of the advantages about being a discussant is that it provides the opportunity not only to put one’s own perspective on the data, but also to be somewhat more speculative. I will try to avoid the temptation to stray too far from the science in so doing. In his paper Voas discusses the effectiveness in reducing alcohol-related crashes (to the extent that it is known) of various laws in the United States that have lowered BAC thresholds for some or all of the population. Included was the move from 0.15 to 0.10 percent in the United States (see Voas for a discussion of this issue), Minimum Purchase Age Laws, an 0.04 threshold for commercial drivers, zero tolerance laws for young drivers, and the reduction from 0.10 to 0.08 percent in some states. The Voas paper does not address the effectiveness of reductions in the BAC threshold in other countries such as Canada, Sweden, and Australia. Nor does he draw from the experiences of our neighbor to the north who have not followed the same path when it comes to underage drinking. I will take a moment to discuss what is known from these experiences because I think these changes, and the overall pattern of drinking and driving and alcohol-related crashes in other countries can provide some insights about the mechanisms by which any reductions seen in alcohol-related crashes might be occurring. Although policy is not the purview of this paper, these changes also have important implications for where we go in the future.

Comment on “Implications of research for policy concerning low blood alcohol concentration in traffic safety"

Williams, Allan F.Insurance Institute for Highway Safety 2001

Abstract

Harold Holder nicely summarizes the workshop papers and provides an interesting discussion of the interplay between research and policy in the alcohol area. Noting that lower BAC limits would be justified as policy based on research indicating impairment and increased crash risk with any drinking, Holder offers for discussion four possible scenarios of lower BAC limits with varying levels of enforcement and publicity. Of course, instituting lower BAC limits does not necessarily reduce the problem of alcohol-impaired driving. And as Holder notes, since research clarifying the effects of a policy cannot be done until the policy is at least partially implemented, and the research takes times to complete, the full impact of a policy may not be known until it is fully established, i.e., after the fact. Fortunately, many alcohol policies are instituted at the state level and thus phased in, and researchers can take advantage of the opportunities for natural experiments that arise from this process.

Legal and constitutional issues related to detection

The objective of this paper is to provide a brief overview of constitutional and other legal issues relating to the detection of impaired drivers. For convenience sake, it is written with regard to alcohol impairment, but the legal issues discussed apply to impairment by other drugs. Within the framework of the U.S. Constitution, detection issues give rise to concerns under the Fourth Amendment (search and seizure), the Fifth and Fourteenth Amendments (due process), the Fifth Amendment (self-incrimination), and the Sixth Amendment (right to counsel). Other legal issues include state constitutional law, which may be more protective of defendants’ rights than the federal Constitution, and state statutory and common law, all of which vary considerably by jurisdiction and even within jurisdictions. It is not possible within the scope of this paper fully to address each issue. At best, the major issues will be put into perspective, and the lesser issues will be identified.

Self-reported drinking and driving practices and attitudes in four countries and perceptions of enforcement

A telephone survey of 2,251 drivers was conducted to compare self-reported behavior and attitudes regarding alcohol consumption and driving in the United States with Australia, Canada, and the United Kingdom. U.S. respondents were less likely to say they drank and reportedly drank smaller quantities than respondents in Australia, Canada, and the United Kingdom. Drivers were most likely to have been checked for alcohol in Australia (82%). Respondents supported tough penalties; 45%-60% thought current penalties were not tough enough. Forty two percent in the United States, 26% in Australia, 35% in Canada, and 47% in the United Kingdom thought police were not doing enough enforcement. Results indicate that there is public tolerance for vigorous enforcement of tough laws and that increased enforcement in the United States and elsewhere would be an acceptable means of addressing the problem of alcohol-impaired driving.

Objectives: This investigation sought to test the effectiveness of a statewide ignition interlock license restriction program for drivers with multiple alcohol-related traffic offenses.

Methods: A total of 1387 multiple offenders eligible for license reinstatement were randomly assigned to participate in an ignition interlock program (experimental group) or in the conventional postlicensing treatment program (control group). The arrest rates of these 2 groups for alcohol traffic offenses were compared for 1 year during the ignition interlock license restriction program and for 1 year after unrestricted driving privileges were returned.

Results: Participation in the interlock program reduced offenders' risk of committing an alcohol traffic violation within the first year by about 65%. The alcohol traffic violation rate during the first year was significantly less for participants in the interlock program (2.4%) than for those in the control group (6.7%). However, there was no statistically significant difference between these groups in the second year, after the interlock license restriction was lifted.

Conclusions: Ignition interlock license restriction programs are effective at reducing recidivism among drivers with multiple alcohol offenses, at least while the restriction is in effect.

Police officers' detection of breath odors from alcohol ingestion

Police officers frequently use the presence or absence of an alcohol breath odor for decisions on proceeding further into sobriety testing. Epidemiological studies report many false negative errors. The current study employed 20 experienced officers as observers to detect an alcohol odor from 14 subjects who were at blood alcohol concentrations (BACs) ranging from zero to 0.130 g/dl. Over a 4 h period, each officer had 24 opportunities to place his nose at the terminal end of a 6 in. tube through which subjects blew. Subjects were hidden behind screens with a slit for the tube to prevent any but odor cues. Under these optimum conditions, odor was detected only two-thirds of the time for BACs below 0.08 and 85% of the time for BACs at or above 0.08%. After food consumption, correct detections declined further. Officers were unable to recognize whether the alcohol beverage was beer, wine, bourbon or vodka. Odor strength estimates were unrelated to BAC levels. Estimates of BAC level failed to rise above random guesses. These results demonstrate that even under optimum laboratory conditions, breath odor detection is unreliable, which may account for the low detection rate found in roadside realistic conditions.

Objectives: This investigation sought to test the effectiveness of a statewide ignition interlock license restriction program for drivers with multiple alcohol-related traffic offenses.

Methods: A total of 1387 multiple offenders eligible for license reinstatement were randomly assigned to participate in an ignition interlock program (experimental group) or in the conventional postlicensing treatment program (control group). The arrest rates of these 2 groups for alcohol traffic offenses were compared for 1 year during the ignition interlock license restriction program and for 1 year after unrestricted driving privileges were returned.

Results: Participation in the interlock program reduced offenders' risk of committing an alcohol traffic violation within the first year by about 65%. The alcohol traffic violation rate during the first year was significantly less for participants in the interlock program (2.4%) than for those in the control group (6.7%). However, there was no statistically significant difference between these groups in the second year, after the interlock license restriction was lifted.

Conclusions: Ignition interlock license restriction programs are effective at reducing recidivism among drivers with multiple alcohol offenses, at least while the restriction is in effect.

License plate confiscation for persistent alcohol impaired drivers

Minnesota cancels the registrations and confiscates the license plates of vehicles driven by repeat drinking drivers in a procedure which prior research has demonstrated to be effective in reducing subsequent recidivism. The research reported here concerns the problems experienced in the functioning of this law. Samples of officials and repeat driving under the influence (DUI) offenders were interviewed in Minnesota and in the neighboring state of Iowa, chosen for comparison because its laws also provide for plate confiscation, but using a judicial rather than an administrative procedure. In addition, representative samples of the driving and vehicle registration records of convicted drunk drivers and of routine traffic offenders were analyzed. The research found that evasion of plate impoundment orders by drivers, though apparently easy to accomplish, appeared to be rare. However, the orders were themselves not issued in a large proportion of cases where they were prescribed by statute, potentially weakening the effectiveness of the law. The reasons, with possible countermeasures, are explored in this report.

The North Carolina Governor's Highway Safety Initiative: initial results from "Booze It and Lose It"

The North Carolina Governor's Highway Safety Initiative is a multiyear program intended to reduce motor vehicle crashes and injuries through publicity/enforcement programs aimed at increasing seat belt use, reducing alcohol-impaired driving, and reducing high speed driving. In 1993-94, a two-stage statewide program involving 6,364 seat belt checkpoints and 58,883 citations increased seat belt use to over 80 percent. The first round of a similarly intensive program addressing alcohol-impaired driving is being launched in November 1994. It features a three-week statewide program of heavy enforcement with checkpoints and roving saturation patrols and extensive publicity about the enforcement. Four emphasis areas - cities or counties within the state - are receiving additional treatment. Pre- and post-program on-the-road surveys of drinking and driving, and before and after telephone surveys are being used to measure the initial effects of the alcohol program. This paper describes the development and evolution of the Governor's Highway Safety Initiative, the alcohol program, and survey results documenting the effects of the first of several anticipated cycles of concentrated, highly publicized enforcement.

Effectiveness of administrative license revocation (ALR) laws

Lund, Adrian K.Transportation Research Circular 413 August 1993

Abstract

This paper reports the results of a literature survey of the effectiveness of administrative license revocation (ALR) as a deterrent to drunk driving. It is concluded that there is overwhelming evidence that ALR contributes to both specific and general deterrence of alcohol-impaired driving.

Comments on detection and enforcement (Appendix E1)

Note and comment on "General deterrence of drunk driving: evaluation of recent American policies" (letter to the editor)

Zador, Paul L.; Lund, Adrian K.Risk Analysis 1993

Abstract

Evans et al. recently published estimates based on regression models for the effects on alcohol-related motor vehicle fatalities for seven types of state laws. They reported that there was “no conclusive evidence that any specific form of punitive legislation is having a measurable effect on motor vehicle fatalities” (p.279), and they concluded that “the most striking finding is that mandatory belt use laws and beer taxes may be more effective at reducing drunk driving fatalities than policies aimed at general deterrence” (p. 279). These conclusions differ markedly from those reached by Zabor et al., who found three types of laws, especially administrative license suspension laws, to be effective in reducing alcohol-related fatalities. According to Evans et al., “the primary reason that our econometric results differ from Zabor et al. is that we have employed a fixed-effect specification, which imposes fewer assumptions on the data-generating process than the state-pairs method or the random-effects models used by Zabor et al.” (p.287). When Evans et al. employed a random-effects model for their data, they too found a significant reduction in fatal crashes related to administrative license suspension. Although we agree that the results of our respective studies differed largely because of methodological differences, the differences between the two methods cannot be reduced to differences between fixed-effect and random-effect models because the estimates reported by Zador et al. were not based on random-effect models. The estimates reported in the Journal of Public Health Policy were, in fact, derived using the state-pair method, which compares changes in annual state fatality counts and state laws between adjacent states. Evans et al. apparently limited their discussion of the models in Zador et al. to random-effects models because the random-effect and state-pair methods resulted in similar estimates. However, because the state-pair and the random-effect methods are based on different sets of assumptions, similar conclusions based on the two methods actually tend to support the random-effects model, and refute the claim that the fixed-effect model is more appropriate. At a minimum, the conclusions of Zador et al. could not be dismissed unless the assumptions of both methods were shown to be dubious.

Administrative license revocation laws that work (editorial)

Lund, Adrian K.U.S. Mayor October 12, 1992

Abstract

During the 1980's, more than 700 laws were enacted by states to advance the battle against alcohol-impaired driving. Few of these laws have been studied adequately, but one, Administrative license Revocation (ALR), has been shown to reduce significantly the fatal crashes by alcohol-impaired driving. Thirty-one states and the District of Columbia now have such laws. If yours is not one of them, you should consider that citizens face greater risk of being involved in an alcohol-related crash.

How effective is administrative license revocation

Lund, Adrian K.Traffic Safety July/August 1992

Abstract

The term "ALR" stands for administrative license revocation, but it refers to either the revocation or suspension of a driver's license before conviction for an alcohol-impaired offense. In about half the states with ALR laws, the license is suspended. Either administrative department or, in some cases, the court can remove the license. But the key is, if the police stop a driver who has a blood or breath-alcohol concentration above a certain limit, that driver can lose his or her license prior to a court conviction. Studies show that license suspension deters drivers from repeat crashes and violations. Although many suspended drivers continue to drive, they drive less often and more carefully. One study of the effects of administrative license suspension on specific deterrence found that repeat offenders for DWI decreased in Louisiana and North Dakota.

Confronting drunk driving: social policy for saving lives

Ross, H. LaurenceInsurance Institute for Highway Safety 1992

Abstract

In this controversial book, a noted authority argues that drunk driving cannot be controlled by punishments administered through the criminal justice system alone. Instead, H. Laurence Ross offers a range of practical solutions to the problem, combining criminal deterrence with suggestions that could reduce alcohol use, lessen automobile use in situations involving drinking, and improve automobile safety.

Enforcing alcohol-impaired driving and seat belt use laws, Binghamton, New York

An evaluation of an integrated enforcement program designed to reduce alcohol-impaired driving and increase seat belt use in Binghamton, NY, was conducted. The program's emphasis is on the publicized use of sobriety and seat belt use checkpoints, passive alcohol sensors, and seatbelt law enforcement. A study of the program's first two years shows that a relative overall reduction of about 39% in the number of drivers who had been drinking and were stopped at police checkpoints was sustained from Fall 1988 to Fall 1990; evidence was also found of significantly fewer injury-producing crashes and significantly fewer late-night crashes during months when checkpoints were held. Drivers with high blood alcohol concentrations were relatively unaffected by the program. Seat belt use rose, especially at night. Results suggest that checkpoints may have to be both constant and visible features of enforcement for their benefits to be lasting.

The effectiveness of administrative license suspension laws

License suspension is an effective way to reduce the problems caused by alcohol-impaired driving. Immediate administrative license suspension after arrest has many advantages over both discretionary and mandatory judicial supension and should increase the application of this penalty and its positive effects. There is wide variation in administrative license suspension laws and some are likely to more effective than others. Ways need to be identified and employed to make administrative license suspension laws more effective in promoting both specific and general deterrence.

Fatal crash involvement and laws against alcohol-impaired driving

It is estimated that in 1985 about 1,560 fewer drivers were involved in fatal crashes because of three types of drinking-driving laws. The laws studied were per se laws that define driving under the influence using blood alcohol concentration (BAC) thresholds; laws that provide for administrative license suspension or revocation prior to conviction for driving under the influence (often referred to as "administrative per se" laws); and laws that mandate jail or community service for first convictions of driving under the influence. It is estimated that if all 48 of the contiguous states adopted laws similar to those studied here, and if these new laws had effects comparable to those reported here, another 2,600 fatal driver involvements could be prevented each year. During hours when typically at least half of all fatally injured drivers have a BAC over 0.10 percent, administrative suspension/revocation is estimated to reduce the involvement of drivers in fatal crashes by about 9 percent; during the same hours, first offense mandatory jail/community service laws are estimated to have reduced driver involvement by about 6 percent. The effect of per se laws was estimated to be a 6 percent reduction during hours when fatal crashes typically are less likely to involve alcohol. These results are based on analyses of drivers involved in fatal crashes in the 48 contiguous states of the United States during the years 1978 to 1985.

Effects of license revocation on drunk-driving offenders

Revoking or suspending the licenses of persons convicted of driving while intoxicated has often been claimed to be uniquely effective in reducing subsequent dangerous driving, as indexed by crashes and violations. This finding holds despite the impression that many suspended and revoked drivers continue to drive illegally. The research described here inquires into the operation of license actions. It uses intensive personal interviews with offenders to obtain information concerning the nature and amount of illegal driving and the effects of license deprivation on employment and other aspects of the offenders' lives.

Britain's Christmas crusade against drinking and driving

Ross, H. LaurenceJournal of Studies on Alcohol September 1987

Abstract

Great Britain's 1983 "Christmas Crusade" against drunken drivers, during which the police of England and Wales administered an average of 1350 breath tests daily, is discussed. Although not deliberately planned and organized, the campaign, fueled by press reports, was perceived by many observes to be a national organized deterrent effort. To test the hypothesis that the crusade reduced drunken driving, the index of total automobile crash-related fatalities was used in the analysis. Results showed that the index declined significantly during the month of the crusade, providing support for the hypothesis of deterrent effect. The experience of the Christmas Crusade reinforces the expectation that deterrent interventions involving highly publicized campaigns increasing the certainty of punishment for illegal behavior can be successful over a limited period of time.

Administrative license revocation in New Mexico: an evaluation

Ross, H. LaurenceLaw and Policy January 1987

Abstract

Swiftness of punishment for drivers impaired by alcohol is likely to be increased objectively by administrative license revocation laws. These laws provide that a driver who fails or refuses a breath-alcohol test has his license confiscated on the spot by police, with formal loss of driving privileges following shortly thereafter. This study of New Mexico law looks for evidence of a deterrent impact of administrative license revocation. Interrupted time-series analysis finds a permanent drop in the proportion of driver and pedestrian fatalities involving the presence of alcohol precisely at the time that the law went into effect. However, lack of publicity for the law and the existence of a complex procedure, unpopular with many police, appear to have diminished the law's effectiveness.

Judicial disobedience of the mandate to imprison drunk drivers

Ross, H. Laurence; Foley, James P.Law and Society Review 1987

Abstract

We report here the results of 2 empirical studies of laws mandating a jail term of 48 consecutive hours for repeat-offender drunk drivers. In both cases, noncompliance by judges, abetted by other criminal justice system actors, was extensive, and substantial proportions of offenders were not imprisoned as mandated. We explain these findings as evidence of both a disjunction between formal and operative definitions of the behavior in question -- drunk driving -- and the great difficulty of controlling the discretion of the actors in the criminal justice system.

Liberalization and rationalization of drunk-driving laws in Scandinavia

A review of recent Scandinavian legislation and practice shows that imprisonment is less often used as a penalty for drunk driving and that there is increasing use of fines and therapeutically oriented sentences. Liberalization has not been accompanied by an increase in drunk driving, and punishment remains related to the degree of moral turpitude reflected in the offense. The continued commitment to a criminal law approach seems paradoxical in light of evidence that most violators show alcohol-related pathology.

Deterring the Drinking Driver: Legal Policy and Social Control

Ross, H. LaurenceInsurance Institute for Highway Safety 1982

Abstract

This book explores both practical and theoretical questions. The practical, policy-oriented question concerns the extent to which law, acting as a deterrent, is effective in ameliorating the social problem of drivers impaired by alcohol (hereafter referred to as drinking and driving). The broader, theoretical question concerns the capabilities and limitations of law as an aspect of social control. These two questions are addressed through a review of deterrence-oriented legal innovations aimed at reducing drinking and driving.

The driver's license is an important document; it is held in an esteem bordering on reverence by every 16-year old. The right-privilege it represents – “to operate a motor vehicle legally – is zealously guarded by its owners, and the law books abound with decisions attesting to the diligence of owners in guarding those rights.

The Scandinavian myth: the effectiveness of drinking-and-driving legislation in Sweden and Norway

Ross, H. LaurenceThe Journal of Legal Studies June 1975

Abstract

Throughout the world, people concerned with the problem of drinking and driving have absorbed the impression that in Scandinavia—particularly in Sweden and Norway—that problem has been controlled by means of law. Swedish and Norwegian laws on drinking and driving have, in the past, been distinguished from the laws of other nations by their use of prison as the routine penalty and by the prohibition, not of impairment while driving, but of attaining a specified level of blood alcohol as determined by scientific tests of bodily substances. To date, however, very little information other than personal experiences and anecdotes has been provided by the Scandinavians and their admirers to support the claim that the Swedish and Norwegian approach has deterred drinking drivers. This report presents the findings of a three-month visit to Scandinavia for the purpose of obtaining systematic evidence concerning this deterrence hypothesis for evaluation by the technique of interrupted time-series analysis. The visit found that the widespread belief in the deterrent effect of the Swedish and Norwegian laws has little solid support. The arguments appearing in the Scandinavian literature are inconclusive, and application of the interrupted time-series method to the available data does not furnish support for the deterrence hypothesis. The impression that there is strong and convincing evidence to believe that the Scandinavian laws have deterred drinking and driving is false. This impression may be fairly characterized as “the Scandinavian myth.”

How drivers prevented from driving would reach work: implications for penalties

The validity of the assumption that loss of a driving license would result in economic hardship for most drivers was examined. Persons who drive to work were asked how they would reach work if a broken leg prevented them from driving. Only 21 per cent said they would not be able to make other travel arrangements. Of those who thought they could find other transportation, two-thirds said the alternative would cost no more than driving themselves. Less than one-fifth said the time required would be more than an additional half hour per day. The results indicate that policies and practices related to license suspension and revocation should not be based on an assumption that job loss or economic hardship would be experienced by most drivers if they were to lose their driving privileges.

Blood alcohol concentrations among Scandinavian drivers: data from the northern countries in international perspective

Ross, H. LaurenceBlutalkohol 1975

Abstract

The study reports the results of an effort to obtain data on blood alcohol concentrations among drivers in Norway, Sweden, Denmark and Finland. A search was made in these countries for studies performed on random or representative samples of (1) drivers fatally injured in crashes; (2) drivers seriously injured in crashes; and (3) drivers not involved in crashes. Only one study, limited to the city of Oslo, was found of drivers not involved in crashes. Sweden and Denmark have produced a scattering of broader but still incomplete studies of fatally injured drivers. A very few small-scale studies of seriously injured drivers were found in Sweden and Norway. Finland has produced no systematic studies on these topics. With some consistency the studies of fatally injured drivers suggest that elevated blood alcohol concentrations are less common in Sweden and Denmark than in the United States. The lone study of drivers not involved in crashes finds an extremely low prevalence of blood alcohol concentrations, in broad international context. However, the studies of injured drivers are not completely in accord with the picture based on the other populations. Although one can speculate that alcohol may be less prominent in motor vehicle crashes in Scandinavian countries than in many other countries, it is improper to infer without further information that the Swedish and Norwegian laws have produced this result.

Jail sentences for driving while intoxicated in Chicago: a judicial policy that failed

Uses the interrupted time series to study the effect on fatalities in Chicago of the highly publicized use of seven day jail sentences as a countermeasure against drunk driving during the winter and spring of 1971. This study is based on data collected from police, coroner, and court records. During the study period magistrates in Chicago's traffic courts were directed to sentence persons convicted of driving while intoxicated to seven days in jail and one year license suspension. To measure the possible effect of simultaneous events, data were also collected from Milwaukee to see if comparable trends could be found. The analyses concludes that change in motor vehicle fatalities during the crackdown was only a chance variation from the fatality rate over the preceding five years.

Screening drivers for alcohol -- an application of Bayes' formula

This paper shows that the criteria under which the drivers can be required to take a breath-alcohol screening test become extremely important when the screening test results are subject to some error. Combining the data from two published studies clearly illustrates the excessively high rates of false arrests which may occur if poor screening methods are employed to screen randomly selected drivers.

Data from all highway fatalities of appropriate age and duration of survival in Alameda and Sacramento Counties. Calif., during January through March and October through December, 1960-67, were considered. Autopsies and blood alcohol determinations were completed on over 98 percent of the fatalities studied. Police reports were available in the coroners' offices. Police estimates of drinking by fatally injured drivers and pedestrians as recorded on police reports were compared with actual blood alcohol concentrations determined by the coroner. Over 20 percent of the time, alcohol was not mentioned in the police report. When alcohol was mentioned, its presence was usually underestimated. Alcohol was least likely to be reported among persons age 60 or older, pedestrians, nonresponsible fatalities, and drivers of new cars. It was most often reported among younger persons, drivers responsible for two-vehicle crashes, and drivers of older cars. One figure, four tables, and 11 references are included.

Driver license suspension ...a paper tiger

Hricko, Andrew R.The Police Chief February 1970

Abstract

The vast majority of laws against habitual traffic law violators or drinking drivers are directed toward penalties in the form of fines and suspension or revocation of driver licenses. However, research indicates that in many cases the withdrawal of the driving privilege is a mere paper transaction; the suspended or revoked driver continues to drive without a license. the following studies are cited: (1) in a 1968 study in California, of 1,326 suspended and revoked drivers, 33% of the suspended and 68% of the revoked drivers continued to drive; (2) in Oregon, 25% of those convicted of driving under the influence had a suspended license or none at all; (3) in Michigan, from the results of a 'spot check' it is estimated that 60,000 drivers (about 1 1/2%) are driving without a valid license; and (4) a study of 72 drivers responsible for fatal accidents indicated 3 had no license and 13 others had been cited at least once for driving while licenses had been revoked. a discussion is presented of where the fault lies, with the law enforcement officers, the courts, motor vehicle administration, or the laws themselves. emphasis is placed on the dearth of research in this field to determine the extent of the problem and possible solutions to it. New methods of control should be devised and more efficient application of legal tools is vitally needed.

The problem drinker and driving: questions of strategy in countermeasure choice and development.

Haddon, William Jr.Proceedings of a Conference on Community Response to Alcoholism and Highway Crashes 1970

Abstract

Since the 1968 Alcohol and Highway Safety Report, previously distributed to the attendees at this conference, well documents the very large contribution of problem drinkers to crashes in which alcohol plays a role (and especially to those most severe), I will not cover the same ground now. Rather, I will outline a few of the principal strategic questions that should illuminate consideration of countermeasures, indicate some of their present answers, and, in addition, hazard a few guesses as to the flavor of some of the future findings concerning them. Before centering on the abusive drinker per se, however, it is essential to recognize that highway safety is a social issue because of a social end result, the end result of damaged people and property. Therefore, anything that contributes to the reduction of that end result, for instance: disconnecting the abusive drinker from highway use; modifying the steering shaft or rigid roadside pole that favors his injury, or that of others he involves; making vehicles less delicate, without reducing the crash protection; they provide; or ensuring far better emergency services, is a legitimate countermeasure.

Baton Rouge project: Where to from here?

British pre-arrest breath tests -- constitutional in the United States?

Hricko, Andrew R.Traffic Digest and Review December 1969

Abstract

The rising highway death and injury toll and a greater public awareness that a substantial portion of this problem can be attributed to drunk drivers have intensified legislative action to remedy the situation. A total of 26 States have already passed implied consent legislation. In search for a legal tool to assist the police in their investigation of driving while intoxicated cases, legislators and safety officials are examining the feasibility of a law similar to the one enacted in the United Kingdom, the Road Safety Act of 1967. The British statute provides that an officer may require any person driving or attempting to drive a motor vehicle to provide a specimen for a breath test if the officer has reasonable cause to suspect him/her of having alcohol in his/her body or to suspect him/her of having committed a moving violation, or if an accident occurs. The article suggests that the constitutional issues of self incrimination, unreasonable search and seizure, and due process, which could be raised in breath test cases, involve judicial questions determined through consideration of set factual situations. Therefore, it is difficult to predict their application unless the exact factual situation is known. However, a properly drawn statute providing for an investigative breath test following an accident or based upon reasonable suspicion of drunk driving does not appear to present insurmountable constitutional barriers. The article includes 34 footnotes and a draft statute.

Deterrence of drinking and driving in France: an evaluation of the law of July 12, 1978

This report describes a study of the effects of a Scandinavian-style law concerning alcohol-impaired driving. The past two decades have seen the adoption throughout most of the developed world of drinking-and-driving laws based on principles originally developed in Norway and Sweden. The French law of July 12, 1978, was a part of this general development. Interrupted time-series analysis of French data on crash-related injuries and fatalities shows that the 1978 law had a notable deterrent effect, but that the effect was not permanent.

Detecting breath odor from alcohol consumption

Police officers frequently use the presence or absence of an alcohol breath odor for decisions on proceeding further into sobriety testing. Epidemiological studies report many false negative errors. The current study employed 20 experienced officers as observers to detect an alcohol odor from 14 subjects who were at blood alcohol concentrations (BACs) ranging from zero to 0.130 g/dl. Over a 4 h period, each officer had 24 opportunities to place his nose at the terminal end of a 6 in. tube through which subjects blew. Subjects were hidden behind screens with a slit for the tube to prevent any but odor cues. Under these optimum conditions, odor was detected only two-thirds of the time for BACs below 0.08 and 85% of the time for BACs at or above 0.08%. After food consumption, correct detections declined further. Officers were unable to recognize whether the alcohol beverage was beer, wine, bourbon or vodka. Odor strength estimates were unrelated to BAC levels. Estimates of BAC level failed to rise above random guesses. These results demonstrate that even under optimum laboratory conditions, breath odor detection is unreliable, which may account for the low detection rate found in roadside realistic conditions.

Analyses of the relationship between blood alcohol and nasal breath alcohol concentrations: implications for assessment of trauma cases

To prevent serious complications and facilitate efficient and effective management of patients admitted to the emergency department or intensive care settings, it is extremely important to differentiate, quickly, between elevated concentrations of alcohol in the blood and compromised neurological status due to brain injury or other pathology. This research analyzed the relationship between blood alcohol concentrations (BACs) estimated from venous blood samples and those estimated from breath samples that were obtained using the Alco-Sensor III device with an attached tube for passive nasal breath sampling. Blood and breath samples, as well as brief medical histories and demographic and environmental data, were obtained and recorded for 35 adult trauma patients admitted to two major urban emergency departments. Passively expired nasal breath provided an excellent estimate of BAC measured from venous blood (range, 0 to 0.32) as evidenced in the extremely high regression coefficient (r = 0.99; slope = 1.22; p less than 0.0001). BAC assessment and monitoring, through the application of passive nasal breath sampling, provides a means of rapidly estimating BAC, and thus can facilitate diagnosis and the initiation of appropriate management and treatment.

Profiles of tetrahydrocannabinol metabolites in urine of marihuana users: preliminary observations by high performance liquid chromatography-radioimmunoassay

Metabolic profiles of 11-nor-9-carboxylic acid-delta 9-tetrahydrocannabinol (COOH-THC) and other THC metabolites were determined in an infrequent and a frequent marijuana user by high performance liquid chromatography-radioimmunoassay (HPLC-RIA). In the infrequent user, no unconjugated COOH-THC was detected in urine samples for the first 8 h following smoking, whereas this metabolite was detected in the urine samples from a frequent user. A metabolite was also detected in the frequent user, which was not present in the urine sample from the infrequent user.

The disposition of tetrahydrocannabinol, 11-hydroxy-tetrahydrocannabinol and 11-nor-9-carboxylic acid tetrahydrocan in frequent and infrequent marijuana users

Peat, Michael A.Insurance Institute for Highway Safety 1985

Abstract

Plasma concentrations of THC, OH-THC and COOH-THC were measured after frequent and infrequent marijuana users smoked a single marijuana cigarette containing 1.8% THC. Plasma THC concentrations of greater than 1 ng/ml were detected for at least six hours in frequent users compared to two hours in infrequent users and COOH-THC concentrations of greater than 10 ng/ml were measured for at least six days in frequent uers. For THC t1/2 a2 was significantly longer in frequent users when compared to infrequent users. Pre-smoking plasma concentrations of THC and COOH-THC ranged from 0.4 to 1.6 ng/ml and from 11 to 83 ng/ml respectively in frequent users. Of the COOH-THC excreted in the urine over fourteen days, 51% was excreted in the first 24 hrs in infrequent users and 49% in frequent users. THC was detected in saliva samples from frequent users for at least 8 hrs. From our study the use of dispositional data to estimate the time of last smoking would be unreliable unless an accurate drug history of the subjects i s known.

The stabilities of delta 9-tetrahydrocannabinol (THC) and two of its metabolites, 11-hydroxy-delta 9-tetrahydrocannabinol (HO-THC) and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (COOH-THC), were determined in blood and plasma stored at -10 degrees C, 4 degrees C, and room temperature. Each of the cannabinoids was added to freshly-drawn blood and plasma to give concentrations of 20 ng/mL. Two-mL aliquots were stored in silanized tubes and the cannabinoid concentrations were monitored by gas chromatography/mass spectrometry over a 6-month period. No significant changes were observed in the concentrations of the cannabinoids for the first month of storage. However, the concentrations of THC and HO-THC in blood stored at room temperature had decreased significantly at 2 months. No statistically significant changes were detected in cannabinoid concentrations in plasma or blood stored at 4 degrees or -10 degrees C for up to 4 months. After 6 months at room temperature, the blood concentrations of THC and HO-THC had decreased by 90 and 44%, respectively, whereas the concentration of COOH-THC was not significantly different from the control. The possibility of loss of cannabinoids from blood due to adsorption onto the grey stoppers used in Venoject tubes was also investigated. Over a 24-hr period, no significant differences were detected in any of the cannabinoid concentrations regardless of sample size (1.3 or 8 mL), differences in temperature (-10 degrees C, 4 degrees C, or room temperature), or extent of contact with the tube's stoppers.

Detection of drinking: a neglected element in DWI enforcement

Voas, Robert B.Insurance Institute for Highway Safety October 1983

Abstract

A strong emphasis is being placed on general deterrence to drunken driving by the National Highway Traffic Safety Administration, the federal government, through the President’s Commission on Drunk Driving and by the states, through new legislation strengthening drunk driving laws, and appropriations providing for increased enforcement effort. While considerable emphasis is being given to enforcement and to producing general deterrence, relatively little has been done to study the nature of the general deterrent effect or to produce improved enforcement technology. There are, however, three notable exceptions to this general statement: 1) breath test development companies have produced small, portable preliminary test devices which are highly accurate; 2) under a NHTSA contract (Harris, et al., 1980), the driving behaviors which are most likely to indicate that the vehicle operator is impaired have been studied and compiled in a manual for traffic enforcement officers; and, 3) with NHTSA support (NHTSA, 1982), a new sobriety testing technique making use of a Nystagmus (small involuntary movements of the eye) has been developed and embodied in a training program for application to officers on DUI assignment.

In a carefully controlled drinking situation there was great individual variation in peak blood alcohol concentrations (BACS) for given doses of alcohol. Alcohol nomograms and tables based on average results from such studies could be misleading since they could frequently result in serious underestimates or overestimates of peak BACS.

Response of breath-alcohol analyzers to acetone

Quantitative evidential breath-alcohol analyzers and screening testers in each of the five current categories of analytical principle were examined for response to dynamically-generated acetone vapor concentrations of 3, 100, 150, 350, and 600 micrograms/210 Liters. Nine of the 13 instruments tested were unaffected by acetone at any of these concentrations; three solid-state (Taguchi) sensing devices and one device employing single-wavelength infrared spectrometry displayed responses to acetone at the two highest tested concentrations. In view of a breath-acetone literature survey for ambulatory subjects and other considerations, response of the tested devices to acetone is not considered to be a significant problem in breath-alcohol analysis for traffic law enforcement purposes.

Drugs and driving: a systematic analytical approach

To collect useful epidemiological data about drug involvement in highway safety, it is essential that sensitive and specific analytical procedures be used to establish the presence of and to determine the concentrations of drugs and metabolites in samples collected from drivers. This paper describes a comprehensive and systematic screening procedure requiring 6 mL of blood, which has been used for the analysis of samples collected from injured and fatally injured drivers. The procedure uses radioimmunoassay, gas chromatography with selective detectors, and high performance liquid chromatography. Drugs and metabolites presumptively identified are then confirmed primarily using gas chromatography--chemical ionization mass spectrometry.

Experimental measurements were performed on 247 healthy adult subjects on end-expiratory breath temperatures, vital capacity volumes, full expiratory volumes after normal inhalation, and breath-throughput volumes and breath inlet pressures for several quantitative evidential breath-alcohol analyzers. The data will facilitate more rational design and effective use of breath-alcohol analyzers. Breath pressures were measured with a Magnehelic Model 2050C direct-reading differential pressure gauge, and breath exit temperatures at the mouth were measured with a Digitec Model 5810 digital thermistor thermometer. Breath volumes were measured with a Model 06001 9-liter water-displacement respirometer modified with a Model 20013 rotary motion potentiometer. Breath throughput volumes were measured with a Model 2207001 Volumeter. Breath throughput volumes and breath inlet pressures for several breath-alcohol analyzers were measured at the breath inlet point. The quantitative evidential breath-alcohol analyzers used in the studies were breathalyzer Model 900 A, intoxilyzer Model 4011, ALBERT Model J2A, and Department of Transportation A.S.D. The statistical analysis of the data was conducted with generally accepted statistical methods. The five data tables should permit more rational design and more effective use of breath-alcohol analyzers and facilitate improved evaluation of the results of experimental studies with breath-alcohol analyzers.

Postmortem plasma luteinizing hormone levels and antemortem violence

Luteinizing hormone (LH) levels were determined in postmortem blood samples obtained from twenty-eight men who sustained sudden traumatic deaths. Violent antemortem behavior (committing suicide by gunshot or hanging, or killed during a violent attack or physical struggle) was associated with significantly higher LH levels than nonviolent antemortem behavior (pedestrians struck by vehicles, crime victims, and those shot during verbal arguments). Within both the violent and nonviolent groups, LH levels were higher in men with detectable alcohol in blood than in men with no alcohol in blood but these differences were not statistically significant. In the nonviolent group, men without alcohol in blood had LH levels within the normal range for healthy adult males. The stability of LH was established in serial studies of normal human male blood specimens over a range of temperatures and time durations comparable to conditions in postmortem blood sampling procedures. These findings suggest that postmortem LH levels in males may be a biological indicator of violent behavior immediately preceding death.

delta 9-Tetrahydrocannabinol and two of its metabolites, 11-hydroxy-delta 9-tetrahydrocannabinol and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol, can be measured in a single 1-ml sample of blood, plasma, or urine by a new assay which combines a relatively rapid extraction procedure with capillary column gas chromatography and negative ion chemical ionization mass spectrometry. Deuterium-labeled analogs of each cannabinoid are added to the physiological specimen as internal standards. Two extracts are obtained from each sample: a neutral fraction containing delta 9-tetrahydrocannabinol and 11-hydroxy-delta 9-tetrahydrocannabinol, and an acid fraction containing 11-nor-9-carboxy-delta 9-tetrahydrocannabinol. The neutral fraction is derivatized by treatment with trifluoroacetic anhydride; the acid fraction is first treated with BF3-methanol followed by reaction with trifluoroacetic anhydride. Under electron-capture chemical ionization conditions the derivatized delta 9-tetrahydrocannabinol and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol give abundant molecular anions ideally suited for selected ion monitoring. The negative ion chemical ionization spectrum of the HO-THC-trifluoroacetate shows no molecular anion. Consequently, quantitation of the hydroxy metabolite is achieved by monitoring a fragment ion formed by loss of CF3CO2 from its molecular anion. The limits of reliable measurement are judged to be 0.1 ng ml-1 for 11-nor-9-carboxy-delta 9-tetrahydrocannabinol, 0.2 ng ml-1 for delta 9-tetrahydrocannabinol and 0.5 ng ml-1 for 11-hydroxy-delta 9-tetrahydrocannabinol. Four examples are given of the application of the assay to the analysis of specimens of medico-legal importance.

GC/MS assays for abused drugs in body fluids

This monograph presents a collection of methods for the quantitative analysis of several important drugs of abuse by the technique of gas chromatography-mass spectrometry (GC/MS). The material is arranged textbook fashion, by chapters on specific drugs, to assist researchers in setting up GC/MS assay procedures in their own laboratories. These assays are particularly suited to basic studies on the pharmacology and pharmacokinetics of drugs of abuse. Forensic toxicology, which sometimes requires the highly sensitive and specific sample analysis provided by GC/MS, is another important area of application. Even when an alternate method such as immunoassay is available for such analyses, GC/MS is often the only means of providing a confirmation assay. The sensitivity and specificity of GC/MS are especially critical to studies on the impact of drugs on traffic safety. In addition, demand for legislation relating to drugs and highway safety is increasing, and enforcement of such laws will necessitate appropriate sample assays. The unique characteristics of the GC/MS analytical method make it the only means of determining drug levels under certain circumstances. The inherent complexity of the technique, however, often dissuades investigators from embarking on studies that involve its use. At a time when basic questions underlying drug abuse call for increasingly sophisticated methods of data acquisition this monograph should provide the information needed to make one of these procedures easier to establish and to encourage new areas of research.

Breath-alcohol simulators: scientific basis and actual performance

Commercial breath-alcohol simulators were studied to determine their suitability as calibrating devices and for providing control specimens in breath-alcohol analysis. The best-fit exponential equation for the air/water partition of ethanol was found to be y = 0.0145 + 0.06583x, where x = temperature and y = Ka/w x l03. Temperature, volume, pressure, and alcohol depletion of simulators and their effluents were measured. The consequences of temperature fluctuations upon effluent-alcohol concentration were determined, as was the number of times a simulator can be used with various breath-alcohol analyzers before reaching 1% alcohol depletion.

Detection of tetrahydrocannabinol in blood and serum using a fluorescent derivative and thin-layer chromatography

A thin-layer chromatographic method is described for the detection of delta-9-tetrahydrocannabinol in blood and serum. The procedure utilizes a reagent, 2-p-chrlorosulfophenyl-3-phenylindone, which reacts with the phenolic group to form a derivative. Following extraction and cleanup, the derivative is prepared and separated from reagent and naturally occurring compounds by thin-layer chromatography. The derivative is then detected by spraying the thin-layer plate with an alkoxide spray which produces a fluorescent spot visible under long wave ultraviolet light. The method can detect 0.2 ng/ml of tetrahydrocannabinol in 5 ml of serum and is suitable for routine screening.

Excretion of urinary cannabinoids after marihuana smoking (abstract)

Urinary cannabinoids were measured by homogeneous enzyme iamunoassay in 12 healthy, adult males before and after administration of 0.5(placebo), 10, and 19.8 mg of THC by marihuana smoking, to determine whether and for how long prior marihuana smoking was detectable. TCH uptake was confirmed by linear heart-rate increases during and after smoking. Urine was collected in 6-hr. aliquots for 4+ days. Results of cannabinoids assay were normalized for urine creatinine concentration measured by an automated Jaffe method.

Detection and quantitation of tetrahydrocannabinol in serum

Much research is being performed in the cannabinoid field due to the increasing concern over the use of marijuana among the youth of America and Western Europe. The purpose of this work was to establish a sensitive analytical method for determining THC (active componenet of marijuana) in physiological fluids. Tetrahydrocannabinol occurs in plasma in very low concentrations (3-50 ng/ml) with the peak level starting to decrease ten minutes after smoking. The physiological effects are most evident for a period of two to three hours after smoking. The level of plasma after two hours is about 3 ng/ml cubed. Thus a mehtod is needed which is capable of detecting THC down to 1 ng/ml. The method should be suitable for routine use, sensitive, specific, inexpensive and preferably amenable to quantitative analysis. There are several methods currently available for the detection of an analysis of THC including Electron-capture gas chromatography, Mass spectrocopy, Mass fragmentography, gas chromatorgraphy + Mass spectrocopy, Radioimmunoassay, High pressure liquid chromatography and Thin layer chomatography (TLC). Among all of these TLC is the simplest and least expensive of the techniques and is thus suitable for routine use. However, a previous report using TLC for THC in urine has not been replicated. The basic problem with TLC is sensitivity. Dansyl derivatives of THC give fluorescent spots detectable at 0.5 ng but the spots are unstable to light thus limiting the utility. A TLC method will be described here which is suitable for routine use in the detection of THC in blood, serum or plasma using a new fluorescent derivatizing reagent DIS-CL.

Human pharmacokinetics of ethanol--further studies (abstract)

Method for alcohol determination in biological liquids by sensing with a solid-state detector

Dubowski, Kurt M.Clinical Chemistry June 1976

Abstract

I describe a new method for quantitative alcohol determination in equilibrated headspace gas of biological liquids by means of a solid-state metal-oxide semiconductor (MOS) detector. After equilibration of the NaCl-saturated specimen at 40 degrees C or other convenient temperature in a closed vessel, a Taguchi MOS sensor is momentarily exposed to the headspace vapor. The resulting dc voltage change from the baseline conditions accurately reflects the alcohol concentration of the liquid specimen, and can be read in direct alcohol-concentration units. Calibration is linear to 3.00 g/liter (300 mg/dl). Values for analytical recovery ranged from 98 to 102%. Correlation of results for blood alcohol concentration by this method (yi) and an automated gas-chromatographic reference method (xi) was y, g/liter = 0.991x + 0.014, with r = 0.997 for 103 blood specimens having concentrations ranging from 0 to 2.89 g/liter (0-289 mg/dl), with a mean difference (xi - yi) - -6 mg/liter (0.6 mg/dl). The method is sensitive to 0.01 g/liter (1 mg/dl) and can be readily automated. An internal standard is not required.

Breath-alcohol analysis: uses, methods, and some forensic problems--review and opinion

Mason, M.F.; Dubowski, Kurt M.Journal of Forensic Sciences 1976

Abstract

Presently when one uses the terms “breath analysis,” “breath testing,” or even the unqualified “chemical testing,” people, generally, think of a determination of alcohol in a specimen of breath for medicolegal purposes. (The unmodified term “alcohol” in this article refers to ethanol.) This is because of the notoriety of this application and, perhaps, the strong resentment of many to the police procedures involved. Actually, analysis of breath has been undertaken for a variety of purposes since before the recorded history of man. Thus an almost infinite number of conscious judgments about, or unconscious responses to, components of his inspired breath have been made based on odor, taste, and other sensory effects, many of these crucial for well-being or survival of both man and other animals. A striking example is the functioning of pheromones [1].

Alcohol intoxication and serum osmolality

The relation between serum osmolality and blood-alcohol was studied prospectively in 565 acute trauma patients. The two measurements were closely correlated. It is therefore possible to estimate the blood-alcohol from serum osmolality to assist in the clinical management of acutely injured patients.

I describe a new method for quantitative alcohol determination in equilibrated headspace gas of biological liquids by means of a solid-state metal-oxide semiconductor (MOS) detector. After equilibration of the NaCl-saturated specimen at 40 degrees C or other convenient temperature in a closed vessel, a Taguchi MOS sensor is momentarily exposed to the headspace vapor. The resulting dc voltage change from the baseline conditions accurately reflects the alcohol concentration of the liquid specimen, and can be read in direct alcohol-concentration units. Calibration is linear to 3.00 g/liter (300 mg/dl). Values for analytical recovery ranged from 98 to 102%. Correlation of results for blood alcohol concentration by this method (yi) and an automated gas-chromatographic reference method (xi) was y, g/liter = 0.991x + 0.014, with r = 0.997 for 103 blood specimens having concentrations ranging from 0 to 2.89 g/liter (0-289 mg/dl), with a mean difference (xi - yi) - -6 mg/liter (0.6 mg/dl). The method is sensitive to 0.01 g/liter (1 mg/dl) and can be readily automated. An internal standard is not required.

Studies in breath-alcohol analysis: biological factors

Dubowski, Kurt M.Z. Rechtsmedizin 1975

Abstract

Various biological factors affecting breath-alcohol analysis were studied experimentally. End-expiratory temperatures in 55 healthy subjects were found to range from 32.41 to 35.69 degrees C with a mean of 34.53 degrees C. Forced vital capacity in the same subjects ranged from 1825 to 6550 ml with a mean of 4038 ml, and maximum exhalation after normal inhalation ranged from 1180 to 4550 ml with a mean of 2730 ml. It was found that 65-70% of available breath must be discarded before the alveolar plateau is reached during expiration. End-expiratory (alveolar) carbon dioxide in 155 healthy subjects was 3.5-8.3% by volume (mean = 6.52). After oral alcohol intake, retained mouth-alcohol in 8 subjects had disappeared after 11 minutes without subsequent water-rinsing of the mouth, and after 8 minutes with rinsing. Water condensation in plastic mouthpieces/saliva traps during breath sampling yielded mean weight gains of 13.0, 8.6, and 4.6 mg., respectively, at initial mouthpiece temperatures of 3 degrees C, 22.5 degrees C, and 34.7 degrees C, respectively.

Breath analysis as a technique in clinical chemistry

Dubowski, Kurt M.Clinical Chemistry August 1974

Abstract

Breath possesses unique advantages as a specimen for clinical chemical analyses, including the continuous equilibrium of gases and volatile substances between expired alveolar air and the pulmonary blood circulation. Substances amenable to analysis in breath include O2, CO2, CO, and other gases, volatile organic compounds, and many drugs with sufficiently high vapor pressures at physiological temperatures. Practical aspects of breath sampling and breath analysis are discussed, exemplified by breath-alcohol analysis. The requirements for obtaining breath samples in equilibrium with the pulmonary blood circulation are delineated, and experimental data are presented for the significant breath-sample characteristics bearing on design of breath collection and storage systems (end-expiratory temperature, breath volumes).

Confirmation of the presence of 11-hydroxy-9-tetrahydrocannabinol in the urine of marihuana smokers

Woodhouse, Edward J.American Journal of Public Health 1972

Abstract

The presence of 11-hydroxy- A 9-tetrahydrocannabinol has been identified and confirmed in the urine of marijuana smokers. The analytical methods involved are liquid extraction by organic solvents followed by thin-layer chromatography and mass spectrometry of the thin-layer eluates. The presence of other cannabinoid metabolites is also indicated.

Detection of marihuana components in urine (3375-C)

Woodhouse, Edward J.Insurance Institute for Highway Safety March 1971

Abstract

The objective of this program was to develop a field method for the identification of marhuana smokers. The best color reagents for the detection of marihuana in urine are described. Laboratory and field tests using finger dips and swabs, mouth washes and swabs, and urine specimens have been investigated. Conclusions are presented on th applicability of these tests in identifying marihuana smokers, and recommendations for future research are detailed.

Comments with respect to highway safety research with particular reference to "chemical tests"

Haddon, William Jr.Insurance Institute for Highway Safety October 1961

Abstract

It would be impossible in the time available here to discuss or even to list the many ways in which chemical tests for the presence of alcohol have been, are being and will in the future be used for highway safety research. Such purposes relate to the entire gamut of questions which arise in connection with the uses and misuses of motor vehicles. This follows from the remarkable prominence of the use of alcohol as a factor in motor vehicle accidents, both fatal and non-fatal. As a result the scientific evaluation of almost any other aspect of motor vehicle accident causation requires a determination of the extent of its relationship with the drinking-driving, drinking-accident problem. In view of this, it is noteworthy that in a number of recent, uncontrolled and controlled investigations seeking causes of accidents this has not been done with even minimum adequacy. Fundamentally considered, the “Chemical Tests”, as they are referred to here, are merely a tool, a yardstick, available for the measurement of one characteristic of drivers whether under experimental or non-experimental conditions. There is nothing magical, or unique, about these tests -- they have many parallels in related fields, notably in forensic and clinical medicine – and their use requires, regardless of the purpose for which they are employed, the same competence, care and intelligence as do such other analytical procedures; requirements which must be observed for the work in question to be both scientifically acceptable and practically useful.

Sobriety checkpoints and passive alcohol sensors: law and research

Fields, MicheleInsurance Institute for Highway Safety February 2001

Abstract

Sobriety checkpoints are a valuable component of a comprehensive enforcement strategy aimed at deterring alcohol-impaired driving. Research shows that the key to effective deterrence is the public's perception of the likelihood of being caught in violation of the law. The public has been shown repeatedly to identify checkpoint activity with increased risk of apprehension. Passive alcohol sensors, devices that detect the presence of alcohol in the ambient air near a subject, significantly increase the effectiveness of sobriety checkpoints in two ways: First, they allow officers to quickly dismiss drivers who have not been drinking. Second, officers using sensors at checkpoint lanes identify a higher proportion of drivers who have been drinking than they do without sensors. This allows officers to focus their skills and attention on those drivers who should be further investigated at checkpoints and to determine if probable cause for an arrest is present.

Field evaluation of the PAS III passive alcohol sensor

Passive alcohol sensors (PAS) are screening devices designed to sample nonintrusively the ambient air around a driver’s mouth to determine the presence of alcohol. Studies have shown that PAS devices can aid police officers in the identification of impaired drivers, particularly at sobriety checkpoints. Data from a 1996 nationwide survey, in which 5,392 drivers were evaluated for alcohol using both the PAS III (a passive sensor housed in a flashlight) and evidential breath test devices, have allowed the determination of appropriate criteria at various blood alcohol concentrations (BAC) for detecting impaired drivers in the field. Using the appropriate criteria, the PAS III can identify about 75% of the drivers with BACs at or above 0.10%, and 70% at or above 0.08%. This is a vast improvement over the 40-50% detection rate currently achieved by police officers at checkpoints not using sensors. Using the PAS III few drivers would be identified inappropriately. At the criterion recommended for detecting BACs at or above 0.08%, about 14% of drivers with BACs of 0.02-0.05% would be incorrectly identified as having a higher BAC. Field studies have shown that when police officers rely on observation alone about 20% of drivers with low BACs are detained for further evaluation. More widespread use of passive sensors by police officers would aid in the detection of drinking drivers. Sensors also could provide an additional deterrent to the general public if they believe that when stopped by the police after drinking they will be detained for further evaluation.

Laboratory evaluation of PAS III sensor with new pump design

The PAS III passive alcohol sensor was evaluated to determine its effectiveness as a screening device to assist law enforcement officers in identifying alcohol-impaired drivers. Under laboratory conditions, the PAS III achieved its best discrimination of drinking subjects with high blood alcohol concentrations (BACs) of 0.10 percent and low BACs of 0.02 percent when the sensor was held at a distance of 5 inches from the subject. At this distance, the sensor would be expected to correctly identify 95 percent of drinking subjects with BACs of 0.10 percent, and incorrectly identify 1 percent of subjects with BACs of 0.02 percent as having a 0.10 percent BAC. The new design of the PAS III results in improved performance at further test distances compared with an earlier design. The PAS III is expected to correctly identify more subjects having a 0.10 percent BAC at a 10 inch test distance than the previous design did at 5 inches, with a reduction in the percentage of lower BAC subjects misidentified as having a high BAC. Because the BAC threshold varies by jurisdiction and class of driver (i.e., adult drivers, young drivers, and commercial drivers), expected detection rates for the PAS III were also calculated for BACs of 0.08, 0.05, and 0.02 percent. Passive alcohol sensors may be particularly important in identifying drivers at these lower BACs because behavioral evidence of impairment may not be present. A second study indicated that these results can be obtained under laboratory conditions even with relatively inexperienced sensor operators.

Passive alcohol sensors in law enforcement screening for alcohol-impaired drivers

The effectiveness and accuracy of passive alcohol sensors in detecting impaired drivers during routine police traffic stops were assessed. Sixteen police officers in Columbus, Ohio, participated in a study in which passive alcohol sensors were used on alternate nights. On nights with the sensors, the number of drivers with blood alcohol concentrations of 0.10 or greater detected by the officers increased from 69% to 77%. The passive alcohol sensor correctly warned of likely alcohol impairment for 81% of the drivers with blood alcohol concentrations of 0.10 or greater. Only three false positive readings (less than 1%) were obtained. When combined with other field studies, the results indicate a statistically significant increase in the detection of alcohol-impaired drivers when patrol officers use passive alcohol sensors in routine traffic stops. As more states pass laws lowering the per se blood alcohol concentration threshold from 0.10 to 0.08%, the use of passive alcohol sensors will become even more important.

Laboratory evaluation of two passive alcohol sensors

Passive alcohol sensors are screening devices designed to sample nonintrusively the exhaled breath of a person to determine whether or not it contains alcohol and if so approximately how much. Two production passive alcohol sensors (NPAS passive alcohol sensor and the Life-Loc PBA 2000) were evaluated in a laboratory environment to establish appropriate threshold measurements that indicate probable alcohol impairment. The laboratory evaluation was conducted using both instrument types with 12 drinking subjects. Both sensors were able to identify alcohol in exhaled breath with sufficient accuracy to identify persons with high blood alcohol concentrations (BACs). The accuracy of both sensors was related to the distance from the subject's mouth: the further away they were from a subject's mouth the greater the chance that high BACs would not be detected. Under ideal conditions, it was estimated that the Life-Loc sensor could be expected to correctly detect 80% of drivers at 0.10% BAC (99% at 0.15% BAC) as being impaired while incorrectly identifying only about one in eight drivers with BACs of 0.02% (false positives). In comparison, the NPAS sensor could be expected to correctly detect about 75% of drivers at 0.10% BAC (97% at 0.15% BAC) while incorrectly identifying one in five drivers at 0.02% BAC.

Detection of impaired drivers with a passive alcohol sensor

Passive alcohol sensors -- constitutional implications

Fields, Michele; Hricko, Andrew R.The Prosecutor Summer 1986

Abstract

Passive alcohol sensors -- devices that detect the presence of alcohol in a person's normally expelled breath -- can improve enforcement of laws against driving while impaired (DWI). This article explores the law of search and seizure as it may apply to the use of passive alcohol sensors.

Detection of intoxicated drivers during DUI patrol: impact of the passive alcohol sensor

An evaluation of the Passive Alcohol Sensor (PAS) was conducted to determine its usefulness in detecting alcohol-impaired drivers. Ten members of a formal DUI Enforcement Team were trained on the use of the device, and employed it during half of 1120 hours of DUI patrol. Officers were accompanied by field observers, who obtained voluntary breath samples from drivers who were not detained. Breath, blood, or urine samples from arrested individuals were obtained by the police. Based on a sample of 1159 stops, 52 percent of all legally intoxicated drivers were detected when the PAS was not used; 61 percent were detected when the PAS was used. Seventy-five percent of the individuals detained when the device was not used were legally intoxicated (BAC >=.08), 82 percent were legally intoxicated when officers did use the device. Five percent and 4 percent of all drivers with BACs <.08 were detained in cases where, respectively, the PAS was not and was employed. None of these differences was statistically significant. Additional analyses revealed considerable officer variability in the accuracy-of-use of the PAS. Subsequently, the PAS was found to be of statistically significant benefit to officers who obtained comparatively accurate BAC estimates, with a 20 percent improvement over the detection rates achieved during normal patrol without the device.

The development and evaluation of a passive alcohol sensor

Jones, Ian S.Proceedings of the 30th Annual Conference of the American Association for Automotive Medicine 1986

Abstract

Passive alcohol sensors are devices that detect the presence of alcohol by sampling the normally exhaled air in front of a person. They supplement traditional police procedures used to assess whether a driver has consumed sufficient alcohol to be impaired and are not intended to provide a quantitative evidential test. A prototype unit was developed to enable police departments to evaluate the utility of these devices for increasing the initial detection of alcohol-impaired drivers by police in a variety of patrol situations. The prototype uses a fuel cell detector specific to alcohol that minimizes interference from non-alcohol substances, such as cigarette smoke, in the air being sampled. The unit consists of a modified flashlight with an alcohol detector incorporated in the head of the flashlight. A small pump draws a sample of air into the unit, which then gives a digital readout of the amount of alcohol present in the sample. The sensitivity of the unit to the sampling distance from the subject’s mouth was established together with the variability between subjects in laboratory tests with drinking subjects. The passive alcohol sensor was tested at a series of sobriety checkpoints. The results showed that without the sensor police officers detected only 45 percent of drivers with BACs greater than 0.10 percent, whereas with the sensor the detection rate increased to nearly 70 percent. Equally important, the sensor significantly reduced the number of drivers who were unnecessarily detained (i.e., drivers thought to be impaired but who had BACs of less than 0.05 percent) from 18 percent to 8 percent.

Detection of alcohol-impaired drivers using a passive alcohol sensor

Conducted a field survey to determine the efficacy of a new type of passive alcohol sensor developed by the Insurance Institute for Highway Safety (IIHS). Results show that the IIHS sensor, as compared with the Honda passive control sensor, improves the detection rate of drivers with blood alcohol concentrations above 0.05 with a substantial reduction rate in false-positives. Other research shows that another disadvantage of the Honda unit is its greater sensitivity to cigarette smoke and other contaminants.

Laboratory and field tests of a passive alcohol sensing systems; testing the impaired driver: the Los Angeles Police Department approach

With the establishment of a Presidential Commission on Drunk Driving and the passage of national legislation providing for special incentive grants to states which strengthened their enforcement activity, nationwide attention is being given to enforcing drinking driving laws. Recent emphasis has been upon creating general deterrence by increasing the perceived risk of arrest and punishment for drunk driving.

Sampling procedures and survey methodologies for the 1996 survey with comparisons to earlier national roadside surveys

This article describes the multistage sampling system employed in the 1996 national roadside survey and compares it to the sampling methods employed in the two prior surveys in 1973 and 1986. Also described are the data collection procedures at the selected sites, the breath-test devices used to collect blood alcohol concentration (BAC) data, and the methods used to impute BAC values where breath-test measures were not obtained. Overall, almost twice as many (6,298 in 1996 compared to 3,698 in 1973 and 3,043 in 1986) drivers were interviewed in the most recent national survey as in the previous efforts. The procedures implemented in the three surveys are sufficiently similar to permit comparison of these surveys conducted at 10-year intervals.

Drinking and driving in the United States: the 1996 national roadside survey

Following the same general principles of its two predecessors in 1973 and 1986, the 1996 National Roadside Survey of weekend, nighttime drivers in the 48 contiguous states interviewed and breath tested over 6000 noncommercial four-wheel vehicle operators between September 6 and November 9, 1996. Results indicated that the total number of drinking drivers fell by about one-third between 1986 and 1996; however, there was no significant change in the number of drivers at blood alcohol concentrations (BACs) at or above 0.05. Compared to 1973, the proportion of women drivers on the roads during weekend nights has increased significantly. Moreover, relative to males, the proportion of female drivers who have been drinking has increased over the last decade. The number of drivers under the age of 21 with a BAC at or above 0.10 decreased significantly from 1986 to 1996.

Drinking and driving in the United States: the 1996 national roadside survey

Following the same general principles of its two predecessors in 1973 and 1986, the 1996 National Roadside Survey of weekend, nighttime drivers in the 48 contiguous states interviewed and breath tested over 6000 noncommercial four-wheel vehicle operators between September 6 and November 9, 1996. Results indicated that the total number of drinking drivers fell by about one-third between 1986 and 1996; however, there was no significant change in the number of drivers at blood alcohol concentrations (BACs) at or above 0.05. Compared to 1973, the proportion of women drivers on the roads during weekend nights has increased significantly. Moreover, relative to males, the proportion of female drivers who have been drinking has increased over the last decade. The number of drivers under the age of 21 with a BAC at or above 0.10 decreased significantly from 1986 to 1996.

The 1996 U.S. roadside survey and its implications

Williams, Allan F.Proceedings of the 14th International Conference on Alcohol, Drugs, and Traffic Safety 1997

Abstract

In the fall of 1996, the third national roadside survey of drinking and driving in the United States was conducted. Earlier surveys were carried out in 1973 and 1986. Results from the 1996 survey have been represented earlier at this confernece. In this brief report, some comments are made about 1996 survey procedures, and specific survey results and their implications are highlighted.

Roadside surveys in conjunction with sobriety checkpoints

Since the 1970s, law enforcement agencies in the US have become reluctant to participate in standard roadside surveys of drinking-driving. Typically, concerns with liability and the increasing prevalence of violence associated with illegal drug activities are cited as reasons not to participate in such surveys. Hence, an alternative roadside survey procedure has been adopted in some locations. By combining survey procedures with sobriety checkpoints established for enforcement purposes, researchers can obtain the law enforcement cooperation necessary to permit collection of needed data. In September and October, 1994 and January, 1995, roadside surveys in conjunction with enforcement checkpoints were conducted in 15 North Carolina counties. These surveys sought (1) to provide a population-based estimate of drinking-driving in the state and (2) to obtain baseline and follow-up data on drinking-driving in 4 areas targeted in a multi-faceted intervention. Surveys conducted in conjunction with enforcement checkpoints differ from those not associated with enforcement actions in several ways. This paper focuses on these differences, emphasizing both the advantages and disadvantages of such cooperative ventures. Political, logistic, and research dimensions of the different procedures are discussed. It is concluded that, on balance, combining surveys with enforcement constitutes a viable alternative procedure for obtaining valid BAC data from the driving public.

Changes in the incidence of alcohol-impaired driving in the United States, 1973-1986

Studies of motor vehicle fatality data have indicated that alcohol involvement in fatal crashes has declined substantially in the United States since 1980. To determine the actual incidence of alcohol-impaired drivers on U.S. roads, a national roadside survey using portable breath-testing devices was carried out in 32 localities in the spring of 1986. The same sampling design and survey procedures used in a 1973 national roadside survey were followed as much as possible. The 1986 survey found 3.1% of the late-night weekend drivers to have a blood alcohol concentration (BAC) of 0.10% or more, compared to 4.9% of drivers in 1973. Similarly, 8.3% of the 1986 drivers were at or above 0.05% BAC, compared to 13.5% in 1973. The data indicate that the incidence of alcohol-impaired driving on weekend nights has fallen by one-third or more in the United States since 1973 and that the decline affected most population subgroups.

Low-manpower checkpoints: Can they provide effective DUI enforcement in small communities?

Objective: Sobriety checkpoints can be effective in reducing alcohol-impaired driving. Checkpoints are underutilized, however, partially because police believe a large number of officers are required. This study evaluated the feasibility and impact of conducting small-scale checkpoints in rural communities.

Methods: Law enforcement agencies in two counties agreed to conduct weekly checkpoints for one year. Two nonadjacent counties did not undertake additional checkpoints. Evaluation included public-awareness surveys and roadside surveys (including blood alcohol concentration [BAC] measurements) of weekend nighttime drivers.

Results: Relative to drivers in the comparison counties, the proportion of drivers in the experimental counties with BACs >0.05% was 70% lower. Drivers surveyed at driver's license offices in the experimental counties after program implementation were more likely to report seeing or passing through a checkpoint and were more aware of publicity on driving under the influence (DUI) enforcement.

Conclusions: Small rural communities can safely and effectively conduct low-staff sobriety checkpoints on a weekly basis. Such programs can be expected to result in large reductions in drivers operating at higher BACs.

Why are sobriety checkpoints not widely adopted as an enforcement strategy in the United States?

Sobriety checkpoints have been used by police in the United States for at least the past two decades to enforce impaired driving laws. Research has indicated that sobriety checkpoints are effective in reducing drinking and driving and alcohol-related fatal crashes. Despite this evidence, many police agencies have been unenthusiastic about using checkpoints. Information was collected from all 50 states plus the District of Columbia on the use of sobriety checkpoints. A total of 37 states and the District of Columbia reported conducting sobriety checkpoints at least once or twice during the year. Only 11 states reported that checkpoints were conducted on a weekly basis. Thirteen states do not conduct checkpoints either because of legal or policy issues. More detailed information was collected from five states that conduct checkpoints frequently and matched with information from five similar states that conduct checkpoints infrequently. States with frequent checkpoint programs had several common features such as program themes, support from task forces and citizen activist groups, use of a moderate number of police at the checkpoints, and use of all available funding mechanisms (federal, state, local) to support them. States with infrequent checkpoints claimed a lack of funding and police resources for not conducting more checkpoints, preferred saturation patrols over checkpoints because they were more "productive," and used large numbers of police officers at checkpoints. Ways to overcome perceived barriers to checkpoint use are discussed.

Sobriety checkpoints and passive alcohol sensors: law and research

Fields, MicheleInsurance Institute for Highway Safety February 2001

Abstract

Sobriety checkpoints are a valuable component of a comprehensive enforcement strategy aimed at deterring alcohol-impaired driving. Research shows that the key to effective deterrence is the public's perception of the likelihood of being caught in violation of the law. The public has been shown repeatedly to identify checkpoint activity with increased risk of apprehension. Passive alcohol sensors, devices that detect the presence of alcohol in the ambient air near a subject, significantly increase the effectiveness of sobriety checkpoints in two ways: First, they allow officers to quickly dismiss drivers who have not been drinking. Second, officers using sensors at checkpoint lanes identify a higher proportion of drivers who have been drinking than they do without sensors. This allows officers to focus their skills and attention on those drivers who should be further investigated at checkpoints and to determine if probable cause for an arrest is present.

Drinking drivers missed at sobriety checkpoints

Objective: Sobriety checkpoints are an effective deterrent to alcohol-impaired driving although a substantial proportion of drinking drivers who pass through checkpoints are missed. The present study was designed to determine the extent to which police officers correctly identify individuals with blood alcohol concentrations (BACs) at or above 0.05% at checkpoints, and if there are characteristics of drivers, vehicles or checkpoints that are associated with decreased chances of detection.

Method: To determine which drivers are likely to be missed, drivers not detained by police for additional sobriety evaluation were interviewed and voluntary breath samples were provided at 156 sobriety checkpoints in North Carolina.

Results: More than 50% of the drivers with BACs in excess of 0.08% and almost 90% of drivers with BACs in excess of 0.05% were not detained by officers. For drivers with BACs of 0.05% or higher, women and those 35 or younger were more likely to be missed than were men and older drivers. Drivers without passengers were more likely to be missed than those with passengers. Drivers were also more likely to be missed during weekend checkpoints. Similar results were found for drivers with BACs at or above 0.08%.

Conclusions: Alerting police officers to characteristics of drinking drivers more likely to be missed may improve detection rates. In addition, passive alcohol sensors could improve the effectiveness and efficiency of sobriety checkpoints in detecting drinking drivers.

Effect of an intensive sobriety checkpoint program on drinking-driving in North Carolina

This paper examines the effects of introducing sobriety checkpoints on the roads of North Carolina. Known as the 'Boose it and lose it' programme, the setting up of the checkpoints was accompanied by widespread publicity. Random surveys were carried out among drivers entering the checkpoint sites. Prior to the checkpoint programme 1.96% of drivers were found to have blood alcohol contents above the legal limit. Following the introduction of the programme this dropped to 0.9%.

Roadside surveys in conjunction with sobriety checkpoints

Since the 1970s, law enforcement agencies in the US have become reluctant to participate in standard roadside surveys of drinking-driving. Typically, concerns with liability and the increasing prevalence of violence associated with illegal drug activities are cited as reasons not to participate in such surveys. Hence, an alternative roadside survey procedure has been adopted in some locations. By combining survey procedures with sobriety checkpoints established for enforcement purposes, researchers can obtain the law enforcement cooperation necessary to permit collection of needed data. In September and October, 1994 and January, 1995, roadside surveys in conjunction with enforcement checkpoints were conducted in 15 North Carolina counties. These surveys sought (1) to provide a population-based estimate of drinking-driving in the state and (2) to obtain baseline and follow-up data on drinking-driving in 4 areas targeted in a multi-faceted intervention. Surveys conducted in conjunction with enforcement checkpoints differ from those not associated with enforcement actions in several ways. This paper focuses on these differences, emphasizing both the advantages and disadvantages of such cooperative ventures. Political, logistic, and research dimensions of the different procedures are discussed. It is concluded that, on balance, combining surveys with enforcement constitutes a viable alternative procedure for obtaining valid BAC data from the driving public.

A review of federal and state constitutional laws concerning sobriety checkpoints

The differences between federal and state constitutional law are described, using Michigan v. Stitz, the u.S. Supreme Court case deciding the constitutionality of sobriety checkpoints as an example. Differences in the various states' concerning checkpoints are identified, and the highway safety research on the effectiveness of checkpoints is reviewed. Properly conducted sobriety checkpoints are a legal and effectives tool for use in deterring alcohol-impaired driving.

Deterrent effects of roadblocks on drinking and driving

The study was designed to determine the extent to which roadblocks (or "sobriety checkpoints") change public perceptions of the enforcement of drunk driving laws and behavior related to drinking and driving. Two areas with active roadblock programs were studied: Montgomery County in Maryland, and Kent and Sussex counties in Delaware. Montgomery was also compared to adjacent Fairfax County, Virginia, which has had a few unpublicized roadblocks, but has a much higher drunk driving arrest rate than Montgomery. The Delaware counties were compared to seven counties on the nearby Maryland Eastern Shore, where roadblocks have not been held. The data were collected via a telephone survey. Results indicated that roadblocks are highly visible. They were the most frequently mentioned activity when respondents in the four areas were asked if they knew about any nearby activities designed to deal with the problem of drunk driving. More than three-quarters of Montgomery County and Delaware respondents were aware of roadblocks in their county. In areas both with and without active roadblock programs, respondents tended to identify the area with roadblocks as the place where drunk drivers would be more likely to be arrested. The limited evidence from self-reported behaviorial measures does not indicate that the roadblocks have changed the drinking and driving behavior of the respondents. Further research is needed.

The effects of minimum legal drinking age 21 laws on alcohol-related driving in the United States

Objective: To examine trends in alcohol consumption and alcohol-related crashes among people younger than 21 in the United States and to review evidence on the effects of minimum legal drinking age (MLDA) laws.

Methods: Trends in alcohol-related crashes and alcohol consumption among young people were examined, and studies on the effects of lowering and raising the drinking age were reviewed.

Results: MLDA laws underwent many changes during the 20th century in the United States. Since July 1988, the MLDA has been 21 in all 50 states and the District of Columbia. Surveys tracking alcohol consumption among high school students and young adults found that drinking declined since the late 1970 s, and most of the decline occurred by the early 1990 s. These were the years when states were establishing, or reinstating, a MLDA-21. Among fatally injured drivers ages 16-20, the percentage with positive BACs declined from 61% in 1982 to 31% in 1995, a bigger decline than for older age groups; declines occurred among the ages directly affected by raising MLDAs (ages 18-20) and among young teenagers not directly affected (ages 16-17). Almost all studies designed specifically to gauge the effects of drinking age changes show MLDAs of 21 reduce drinking, problematic drinking, drinking and driving, and alcohol-related crashes among young people. Yet many underage people still drink, many drink and drive, and alcohol remains an important risk factor in serious crashes of young drivers, especially as they progress through the teenage years. Stepped-up enforcement of MLDA and drinking and driving laws can reduce underage drinking. Recent efforts to lower MLDAs to 18 and issue licenses to drink upon completion of alcohol education have gained local and national media attention. There is no evidence that alcohol education can even partially replace the effect of MLDA-21.

Conclusions: The cause and effect relationship between MLDAs of 21 and reductions in highway crashes is clear. Initiatives to lower the drinking age to 18 ignore the demonstrated public health benefits of MLDAs of 21.

Impact on industry: Lowering the drinking age to 18 will increase highway crash deaths among young people.

Effects of a college community campaign on drinking and driving with a strong enforcement component

Objectives: A program of publicized intensive enforcement of minimum drinking age law and drinking and driving laws was implemented in a college community. The effects on driving at various blood alcohol concentrations (BACs) were evaluated, particularly for drivers ages 16-24 targeted by the program.

Methods: Objective measures of driver BACs were collected through nighttime roadside surveys before and during the program in the experimental college community and a comparison college community. Logistic regression models estimated the program’s effects on the likelihood of driving at various BAC thresholds in the program community, after accounting for BAC patterns in the comparison community.

Results: relative to the comparison community, consistent reductions in driving at various BAC levels (positive BAC and BAC at least 0.02, 0.05, or 0.08%) were achieved in the experimental community. Reductions were greatest for 16- to 20-year olds (from 66% for positive BAC to 94% for BAC = 0.05%), followed by 21- to 24- year olds (from 32% for positive BAC to 71% for BAC =0.08%) and drivers 25 and older (from 23% for positive BAC to 53% for BAC = 0.08%). All reductions for 16- to 20-year-olds were significant (p < 0.05), and all except the reduction for BAC = 0.08 percent were significantly greater than the corresponding reductions for drivers 25 and older. Reductions for 21- to 24-year-olds were significant for BACs at least 0.02, 0.05, and 0.08 percent, but they were not significantly greater than the corresponding reductions for drivers 25 and older. Although large, reductions for drivers 25 and older were not significant, based on 95 percent confidence intervals.

Conclusions: A college community program with a strong enforcement component produced substantial reductions in drinking and driving among teenagers and young adults and smaller reductions among older adults. It is hoped that this will encourage colleges and communities to incorporate enforcement into interventions directed at alcohol use among young people.

Minimum purchase age laws: How effective are they in reducing alcohol-impaired driving?

Young drivers are less likely than adults to drive after drinking alcohol, but their crash risk is substantially higher when they do. This is especially true at low and moderate blood alcohol concentrations (BACs) and is thought to result from teenagers’ relative inexperience with drinking, driving, and combining the two. Since July 1988, all 50 U.S. states and Washington, D.C., have had laws that require people to be at least 21 years old to purchase alcohol. Many other countries, however, allow people younger than 21 to drink alcohol. Minimum legal drinking ages are 16 to 18 in most European countries, 18 to 19 in Canada, 18 in Australia, and 20 in New Zealand. Laws that establish a minimum age to drink alcohol are the primary legal mechanism limiting teenagers’ access to alcohol. In the United States, zero tolerance laws that make it illegal for people younger than 21 to drive with any measurable amount of alcohol in their bodies, and minimum legal drinking age (MLDA) laws of 21 are the primary legal countermeasures against underage drinking and driving. This paper summarizes trends in alcohol-impaired driving among people younger than 21, the history of minimum legal alcohol drinking age laws, and the evidence of their effects. Laws vary with regard to whether they prohibit the purchase, consumption, or possession of alcohol by underage people (here referring to those 20 and younger). For simplicity, the terms “drinking age” and “minimum legal drinking age,” collectively abbreviated as MLDA, are used to refer to all of these types of laws. The paper focuses primarily on the United States, where the bulk of research has been conducted.

Objectives: Zero tolerance (ZT) laws have been effective in reducing alcohol-related crashes among underage drivers. However, enforcement in some states has not been rigorous, and ZT offenses may not be viewed as serious offenses. On July 1, 1994, the state of Washington implemented a ZT law that allowed police to request a test for alcohol on suspicion of either a ZT or driving-under-the-influence (DUI) offense. The present study examined effects of the ZT law on arrests and case dispositions among underage offenders as a function of blood alcohol concentration (BAC) and post-law patterns of recidivism.

Methods: Times-series analyses examined the effects of the ZT law on trends in arrests of underage drivers between 1991 and 1999. Based on arrest records matched with driver's license records, the effects of the law on dispositions of alcohol-related offenses among underage drivers were examined, and rates of recidivism among underage offenders were examined for the period following the ZT law.

Results: There was a substantial increase in arrests of underage drivers beginning immediately after implementation of the ZT law, especially among drivers with low BACs. The types of court or administrative dispositions received by underage offenders changed markedly after the ZT law was implemented. Underage offenders with lower BACs became far more likely to receive alcohol-related convictions and/or license suspensions. However, the percentage of underage offenders with higher BACs receiving DUI convictions declined as some of these offenders received the lesser ZT disposition. After the ZT law, underage offenders with BACs of 0.10 g/dL or higher were more likely to recidivate than those with lower BACs, but appreciable proportions of drivers were re-arrested for another alcohol offense, whatever the BAC and however they were penalized.

Conclusions: Implementation of Washington's law indicates that a ZT law can increase the likelihood that an underage person will be sanctioned for drinking and driving. However, recidivism remains an issue as more than one in four underage drivers arrested with low BACs subsequently were re-arrested.

Underage drinking: frequency, consequences, and interventions

Objectives: To examine the frequency of underage drinking, driving after drinking and alcohol-related crashes, trends in these behaviors, and promising interventions.

Methods: We examined drinking and drinking- and-driving behaviors reported in the United States in the 2001 U.S. National Household Survey of Drug Abuse, the Centers for Disease Control and Prevention 2001 Youth Risk Behavior Survey, the 1992 National Longitudinal Alcohol Epidemiologic Study, and the 1999 National Survey of Drinking and Driving conducted for the National Highway Traffic Administration. We also examined the 1999 European School Survey Project on Alcohol and Other Drugs. Alcohol-related fatal crashes were examined from the U.S. Fatality Analysis Reporting System. Evaluation of interventions to reduce teenage drinking and driving after drinking were reviewed.

Results: In the United States, 19% of youth ages 12-20 consumed five or more drinks on an occasion in the past 30 days. Although European nations have lower legal drinking ages (16-18) than in the United States (21), similar proportions engage in underage drinking. In two-thirds of European countries, a greater percentage of 15-16 year-olds drank five or more drinks on an occasion in the past month than in the United States. In both the United States and Europe, the earlier people begin to drink, the greater the likelihood of developing alcohol dependence and other alcohol-related problems, including alcohol-related crash involvement, during adolescence and adult years. During the past 20 years alcohol-related traffic deaths among people younger than 21 have been cut in half in the United States, but progress has halted since 1995 and the problem is still large. Interventions shown by research to reduce alcohol-related crashes among youth include raising the legal drinking age to 21, zero tolerance laws, and some interventions that are family, school, or community based.

Conclusions: Despite research showing that a variety of interventions can reduce underage drinking and alcohol-related crash fatalities, the frequency of these behaviors remains high and the average age of drinking initiation is declining in the United States. Efforts are needed to enhance publicized enforcement of underage drinking laws. Comprehensive community interventions that include enforcement of these laws also are needed.

Awareness of zero tolerance laws in three states

Problem: A prior study indicated that zero tolerance laws differ in their enforceability and likelihood of enforcement, with California's law being easier to enforce than New York's, and New Mexico's being the hardest of all. The question is, do these differences in enforcement affect teenagers' knowledge and perception of these laws?

Method: A telephone survey was conducted to investigate awareness of the laws among 17-20 year olds in these three states and perceptions of enforcement.

Results: Estimated percentages of teenagers who knew of the laws were much higher in New York and California (71% and 65%, respectively) than in New Mexico (34%). Perceptions that police were enforcing the law, that licenses could be suspended, and that penalties were often applied were also lowest in New Mexico.

Impact on industry: The potential of zero tolerance laws will not be realized without better awareness among young people. Full enforcement of the laws accompanied by publicity about the enforcement is recommended. Changes to the laws and their application may encourage enforcement efforts.

Enforcement of zero tolerance laws in the United States

By 1998 all states had enacted zero tolerance laws, which prohibit people younger than 21 from driving with any positive blood alcohol concentration (BAC). A review of the law was undertaken to determine whether variations in zero tolerance laws might affect their enforcement. Five states were selected (California, Michigan, New Mexico, New York, and Virginia) that appeared to differ in the ease with which the laws could be enforced. Detailed information on enforcement practices was collected in interviews with police officers and motor vehicle officials. The zero tolerance laws in these states have done little to change the way police identify underage drinking drivers. Consequently, these laws rarely are being enforced independently of the laws against impaired driving aimed at all ages. However, if an officer stops an underage drinking driver, some provisions of the laws can make it easier to issue a zero tolerance citation. For example, in most states an evidentiary test for BAC is required to prove a zero tolerance violation, but in a number of states the implied consent law requires either an arrest for driving while impaired (DWI) or probably cause for an arrest before such a test can be administered. Thus, underage offenders with low BACs cannot be arrested for zero tolerance. By contrast, in California officers can use results from preliminary breath test (PBT) units at the roadside as evidence of zero tolerance if an underage driver is suspected of drinking. Factors that reduce the likelihood of enforcement are discussed.

Graduated licensing in Florida: the .02% BAC driving restriction

Using data gathered through a self-administered survey of Florida high school juniors and seniors in 1996 and 1998, this study examined teens' reported attitudes and behaviors before and after the state's Zero Tolerance law took effect on January 1, 1997. Decreases occurred in reported driving when drinking and reported riding with friends who were drinking. Teen support for the law increased substantially. Significant changes occurred more often for males and for teens in urban and suburban, as opposed to rural, counties.

Underage access to alcohol: sources of alcohol and use of false identification

High school juniors and seniors and college students under the age of 21 were surveyed (N = 4,390) in southeastern New York, a state with generally weak laws regarding underage persons who purchase and possess alcohol, and in eastern Pennsylvania, a "liquor control" state with generally strong laws. Results indicated that more students had obtained alcohol from "friends" than from any other possible source. Approximately half of all students surveyed had attempted to purchase alcohol. Approximately one-third had, at some time, used some form of false identification typically a counterfeit, borrowed, altered or illegally obtained drivers license. The primary objective of the present study was to determine the sources of alcohol for underage persons including direct purchase. High school juniors and seniors and college students under the age of 21 were surveyed in eastern Pennsylvania and southeastern New York, two areas with substantially different laws regarding underage alcohol violations.

Reactions of teenagers and parents to a zero alcohol tolerance law

Graduated licensing applies a series of driving restrictions that are gradually relaxed as the young driver gains experience and becomes more mature. Although there are no results yet by which to judge the effectiveness of such a system, the authors wanted to examine how well the concept is understood, its level of acceptance and the extent of compliance with it. A study is described that examined the 2-stage graduated licensing program implemented in the province of Nova Scotia in 1994. In this program there is a restriction that prohibits drivers in both the learner and newly-licensed driver stages from driving if they have any detectable alchol in their system. The reactions of teenagers and parents to this 'zero tolerance' law are discussed.

Policing underage alcohol sales

This study evaluates an enforcement program targeted at licensed retail sellers of alcohol. The program was a sting or decoy operation in which underage police cadets attempted to purchase packaged beer at randomly selected grocery, convenience, liquor, and drug stores in Denver, Colorado. Stores that sold alcohol to the underage purchasers were subject to fines and beverage license suspensions. During baseline, cadets purchased beer 59% of the time. The purchase rates for successive waves of enforcement conducted over the next 10 months were 32%, 26%, and 26%.

Sales of alcohol to underage purchasers in three New York counties and Washington, DC

A study was conducted in which young males, under the legal alcohol purchase age of 21, attempted to purchase beer at grocery stores and other retail outlets. Underage purchases were attempted at a sample of stores in Washington, D.C.; Westchester County, N.Y.; and Albany and Schenectady counties, N.Y. Beer was sold to the underage purchasers at 97 percent of the Washington, D.C., stores, 80 percent of the Westchester County stores, and 44 percent of the Albany and Schenectady stores, despite the fact that such sales are illegal. Beer was more likely to be sold to the underage purchasers at smaller neighborhood stores in urban areas. Sales were least likely in Albany, which experienced recent police enforcement of the alcohol purchase age laws. Vigorous enforcement of the minimum purchase age laws is needed to reverse the current national trend toward more alcohol-related highway fatalities among youth.

Drinking age laws: an evaluation synthesis of their impact on highway safety

Williams, Allan F.Contemporary Drug Problems Winter 1987

Abstract

This study examined existing evaluations of drinking-age laws to determine the extent to which they provide empirical support for federal and state initiatives to change the legal drinking age. It specifically examined the effects that raising the minimum drinking age has had on traffic accidents, beverage alcohol consumption, driving after drinking, and related concerns for youths younger than the minimum age. A review of 49 documents which evaluated laws raising the legal drinking age revealed that raising the legal drinking age had a direct effect on reducing alcohol-related traffic accidents among youths affected by the laws. Evidence suggests that raising the drinking age results in a decline in both alcohol consumption and driving after drinking for the age group affected by the law. The evidence was insufficient to draw conclusions about the effects of raising the drinking age on youths 16 to 17 years old, border crossings, and other related matters. Literature reviews of earlier evaluations of the effects of lowering the drinking age, however, do give evidence that traffic-accident outcomes increased as a result of changes in the law.

Raising the alcohol purchase age: its effects on fatal motor vehicle crashes in twenty-six states

Raising the legal minimum age for purchasing alcoholic beverages reduces the involvement of youthful drivers in fatal traffic accidents. The analysis used data on all drivers aged 16 through 24 who were involved in crashes in which someone was killed during the years 1975-1984 in the 48 States in the continental United States. The data came from the Fatal Accident Reporting System of the National Highway Traffic Safety Administration. The analysis excluded motorcycle fatalities, crashes involving more than three motor vehicles, and drivers not living in the State in which the crash occurred. The results were based on a total of 159,262 driver fatal crash involvements, of which 87,153 took place between 8 p.m. and 5 a.m. Raising the purchase age was estimated to produce a 13-percent reduction in nighttime driver fatal crash involvements. Various State, age, and year combinations showed 8 to 18 percent fewer nighttime crash involvements than would otherwise have occurred. A much smaller effect occurred for daytime crashes, which involve alcohol much less often. Eighty-one percent of the drivers involved in fatal crashes were male.

Comment on Males

Williams, Allan F.Journal of Legal Studies January 1986

Abstract

Intro: In 1981, the Insurance Institute for Highway Safety studied the effects of raising the legal minimum age for purchasing alcoholic beverages on fatal motor vehicles crashes. Nine states were studied that had raised their minimum purchase ages and for which sufficient data were available for the period after the new law. To rule out the possibility that changes observed in youthful crash involvement in states that raised their purchase ages were merely part of a regional trend, each of the nine states studied was paired with a neighboring comparison state in which the minimum purchase age remained unchanged throughout the study period. To rule out the possibility that changes observed in age groups covered by the laws were part of a trend occurring at other ages as well, age groups covered by the laws were compared to older drivers, to whom the law changes did not apply.

Raising the legal purchase age in the United States: its effects on fatal motor vehicle crashes

Williams, Allan F.Alcohol, Drugs, and Driving 1986

Abstract

Reviews results of studies investigating the effects of raising the age for purchasing alcoholic beverages on the incidence of fatal motor vehicle crashes. It is concluded that raising the alcohol purchase age can contribute to the prevention of alcohol-related motor vehicle crashes among teenagers, but that additional countermeasures directed at the drinking and driving problem among both teenagers and adults are needed.

Adults' views of laws that limit teenagers' driving and access to alcohol

A telephone survey assessed adults' views of laws that limit teenagers' driving and access to alcohol. Interviews were conducted with 606 heads of households containing a person between the ages of 13 and 18 and with 400 heads of households not containing a teenager. Data were weighted So that results could be projected to total US households. Results indicated that two of three parents of teenagers were very concerned about the risk of automobile travel for their children. The majority of adults, especially women, favored measures that would reduce the driving exposure of teenagers and their access to alcoholic beverages. They favored higher licensing ages, night-driving curfews, special probationary licenses for teenagers, and a minimum alcohol purchase age of 21. Parents of teenagers were only slightly more likely than other adults to favor these policies. Support for night-driving curfews and 21-year-old alcohol purchase age laws was more frequent among adults living in states that already have these measures. However, in states without night curfews and 21-year-old purchase ages, about two-thirds still favored these measures. Further, those who favored curfew laws tended to prefer them to start earlier than they presently do in states that have them. About half of the respondents favored licensing ages of 17 or older and 4 out of 10 favored a minimum licensing age of 18. It is concluded that limiting the driving and alcohol-purchasing possibilities of teenagers through legislation could lead to large reductions in teenage crash involvement. Results of this survey indicate that measures to raise the licensing age or to institute night curfews have the support not only of parents of teenagers but also of the great majority of adults.

Drinking and driving among high school students

A questionnaire survey of high school students conducted in 1983 provided information on their self-reported drinking and driving practices. By age 15 the majority reported drinking alcoholic beverages. By age 17 half or more of the males and one-third of the females reported driving after drinking at least once in the past month. About one-quarter of the students estimated that six or more cans of beer would be required to make someone an unsafe driver. Reported frequency of driving after drinking was associated with less time spent on homework and poorer academic performance, working part time, greater participation in social activities, less perceived parental influence regarding their travel, owning a car, driving high mileage, speeding, and having crashes and violations.

The effect of raising the legal minimum drinking age on involvement in fatal crashes

In the early 1970s, more than half of the states in the United States lowered their legal minimum ages—in most cases from twenty-one to eighteen—for the purchase of some or all alcoholic beverages. Research indicated that this legislation resulted in increased involvement of young drivers in crashes. In a study of various states and Canadian provinces that reduced the drinking age from twenty-one to eighteen, significant increases were shown in fatal crashes—particularly in nighttime and single vehicle crashes in which alcohol is most often involved—involving driver under twenty-one, compared with adjacent areas that did not reduce their drinking ages. These increases occurred not only among eighteen- to twenty-year-olds, who were directly affected by law changes, but also among fifteen- to seventeen-year-olds. As a result of these findings and other reports of growing problems related to teenage drivers and alcohol, many states that had lowered their legal minimum drinking ages in the early 1970s began in 1976 to raise them. By the end of 1980, fourteen of the thirty states that had lowered their drinking ages for the purchase of some or all alcoholic beverages had raised them, although not necessarily back to the original limits. In this paper, a study of the effect of raising the drinking age on fatal crashes involving teenage drivers is reported.

Teenage drivers and alcohol use

Williams, Allan F.Research Note 101 1982

Abstract

This Research Note briefly states the extent of the problem of motor vehicle fatalities attributed to teenage drivers, then presents four key facts which summarize existing knowledge concerning teenaged drivers and alcohol use. Since Research Notes have the goal of making information publicly available on a timely basis, for more extensive information on the subject presented the reader is provided with a list of references in support of the conclusions presented.

Blood alcohol concentrations of patrons leaving a college pub

Few patrons leaving a college pub had blood alcohol concentrations equal to or greater than 0.10% and one-third had BACs of 0.05% or greater. Men had higher BACs than women had and were less likely to judge themselves incapable of driving safely.